Dátum: 2024. május 3.

Előadás címe: Understanding Radiation Processing of Astrophysical and Planetary Ice and Atmosphere Analogs

Előadó: Murthy S. Gudipati (Senior Research Scientist, Science Division, NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA)


One of the key goals of astrochemistry is to simulate astrophysical and planetary conditions in the laboratory in order to understand physical and chemical processes that occur in those environments. Astrophysical and planetary conditions range from ultracold molecular clouds to hot exoplanetary atmospheres, covering gas, liquid, and solid phases at ultrahigh vacuum to megabar pressures,  radiation from stars, cosmic rays, and local magnetospheric radiation environments, requiring broad range of researchers to contribute to the field of astrochemistry. Our contribution has been in two fields: (a) physics and chemistry of ice and organics in radiation environments; (b) simulations of exoplanet atmospheres simulating photochemistry at high-temperatures in the gas-phase.


At the Ice Spectroscopy Laboratory (ISL) at JPL, we conducted Lya UV-photolysis of astrophysical ices and showed that the formation of molecules of life such as HCN, formamide, etc., demonstrating that some of the key organic molecules needed for the origin of life could have already formed in the interstellar ice grains [1]. Significant new experimental and observational data are needed to close the knowledge gaps in this area of research, which is critical to test the hypothesis that early bombardment from comets and asteroids about 4 billion years ago would have brought water and organic molecules to Earth kickstarting origin of life on Earth [2-4].


Further research activities in our lab over the past decade simulating radiation processing of planetary ices - atmospheric and surface - will be discussed. Our most recent work on simulating photochemistry of high-temperature exoplanet atmospheres will also be discussed.


Acknowledgment: This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA). Funding from NASA through DDAP, HW, NFDAP, SSW, and XRP programs is acknowledged.



1.            Henderson, B.L. and M.S. Gudipati, Astrophysical Journal, 2015. 800(1): p. 66.

2.            Greenberg, J.M., Instruments, Methods, and Missions for the Investigation of Extraterrestrial Microorganisms, ed. R.B. Hoover. Vol. 3111. 1997. 226-237.

3.            Huebner, W.E. and D.C. Boice, Origins of Life and Evolution of the Biosphere, 1992. 21(5-6): p. 299-315.

4.            Altwegg, K., et al., Science Advances, 2016. 2(5).

Dátum: 2024. március 28.

Előadás címe: Recent advances in space-time shaping, modelling, and characterization

Előadó: Spencer Jolly (Université Libre de Bruxelles)


The measurement and control of ultrashort laser pulses in the spatio-temporal domain is becoming more well-known and increasingly utilized for optimizing and controlling laser-matter interactions. Although devices and techniques have come a long way in the past two decades, there is still progress in terms of either simplifying devices or improving their capabilities. In this talk we will focus on recent advances in space-time shaping and characterization, which often go hand-in-hand, and add some perspective on recent theoretical descriptions of space-time effects and how they may be characterized, and where the future of characterization devices may be going.

Dátum: 2024. március 22.

Előadás címe: Attosecond science at ELI scale

Előadó: Katalin Varjú (ELI ALPS)


The Extreme Light Infrastructure – Attosecond Light Pulse Source (ELI-ALPS), the Hungarian pillar of ELI ERIC [1], is the first of its kind that operates by the principle of a user facility, supporting laser based fundamental and applied researches in physical, biological, chemical, medical and materials sciences at extreme short time scales. This goal is realized by the combination of specialized primary lasers which drive nonlinear frequency conversion and acceleration processes in more than twelve different secondary sources. Thus a uniquely broad spectral range of the highest power and shortest light pulses becomes available for the study of dynamic processes on the attosecond time scale in atoms, molecules, condensed matter and plasmas [2-3].

The attosecond secondary sources are based on advanced techniques of Higher-order Harmonic Generation (HHG) [4-5]. Other secondary sources provide THz radiation or particle beams for plasma physics and radiobiology. A set of state-of-the-art endstations will be accessible to those users who do not have access or do not wish to bring along their own equipment. At the current phase of the project ELI-ALPS welcomes the submission of proposals6 for scientific experiments that will support the ramping up of the broad selection of light sources and experimental stations available. ELI-ALPS provides beamtime as well as technical and scientific support for the experiments.




[2] S. Chatziathanasiou et al., “Generation of Attosecond Light Pulses from Gas and Solid State Media”, Photonics 4, No 26 (2017)

[3] M. Reduzzi et al., “Advances in high-order harmonic generation sources for time-resolved investigations”, Journal of Electron Spectroscopy and Related Phenomena 204, Page 257-268 (2015)

[4] S. Kuhn et al., “The ELI-ALPS facility: the next generation of attosecond sources.”, Topical Review, Journal of Physics B 50 132002 (2017)

[5] S. Mondal et al., “Surface plasma attosource beamlines at ELI-ALPS”, JOSA B 35, A93-A102 (2018)


Dátum: 2024. március 21.

Előadás címe: Introduction to spatio-temporal couplings of ultrashort lasers: metrology and applications: Controlling laser-matter interactions using spatio temporal couplings

Előadó: Fabien Quéré


The accurate temporal characterization of ultrashort laser pulses has now become a routine procedure in all labs working with femtosecond lasers, providing the complex field E(t) of these pulses, and such measurements have become a key tool for the optimization and control of laser-matter interaction experiments. Yet, they are actually insufficient to fully characterize an ultrashort laser beam, which is intrinsically a 3D physical object, described by a  complex field E(x,y,t), where x and y are the spatial coordinates transverse to the propagation direction. In many cases of interest, the spatial and temporal dependences of this field cannot be separated: in such instances the beam is said to exhibit spatio-temporal couplings (STC). Thanks to the work carried out by a few groups in the last decade, measurement techniques and devices are now available to fully determine the field E(x,y,t) in such cases. Furthermore, there are now several striking examples of how to take benefit of carefully controlled STC to finely control laser-matter interaction processes, especially at ultrahigh laser intensities and down to the attosecond time scale. This series of tutorial will provide an accessible introduction to STC, their metrology and a few selected examples of their applications.


Dátum: 2024. március 18.

Előadás címe: Promoting ELI in scientific press

Előadó: Sir Philip Campbell (Fellow of the Royal Astronomical Society; Fellow of the Institute of Physics)


Promoting ELI in scientific press

Dátum: 2024. március 14.

Előadás címe: Introduction to spatio-temporal couplings of ultrashort lasers: metrology and applications: A short survey of spatio-temporal couplings measured on different ultrashort lasers

Előadó: Fabien Quéré


The accurate temporal characterization of ultrashort laser pulses has now become a routine procedure in all labs working with femtosecond lasers, providing the complex field E(t) of these pulses, and such measurements have become a key tool for the optimization and control of laser-matter interaction experiments. Yet, they are actually insufficient to fully characterize an ultrashort laser beam, which is intrinsically a 3D physical object, described by a  complex field E(x,y,t), where x and y are the spatial coordinates transverse to the propagation direction. In many cases of interest, the spatial and temporal dependences of this field cannot be separated: in such instances the beam is said to exhibit spatio-temporal couplings (STC). Thanks to the work carried out by a few groups in the last decade, measurement techniques and devices are now available to fully determine the field E(x,y,t) in such cases. Furthermore, there are now several striking examples of how to take benefit of carefully controlled STC to finely control laser-matter interaction processes, especially at ultrahigh laser intensities and down to the attosecond time scale. This series of tutorial will provide an accessible introduction to STC, their metrology and a few selected examples of their applications.

Dátum: 2024. március 8.

Előadás címe: Introduction to spatio-temporal couplings of ultrashort lasers: metrology and applications: A biased introduction to the spatio-temporal metrology of ultrashort laser beams

Előadó: Fabien Quéré


The accurate temporal characterization of ultrashort laser pulses has now become a routine procedure in all labs working with femtosecond lasers, providing the complex field E(t) of these pulses, and such measurements have become a key tool for the optimization and control of laser-matter interaction experiments. Yet, they are actually insufficient to fully characterize an ultrashort laser beam, which is intrinsically a 3D physical object, described by a  complex field E(x,y,t), where x and y are the spatial coordinates transverse to the propagation direction. In many cases of interest, the spatial and temporal dependences of this field cannot be separated: in such instances the beam is said to exhibit spatio-temporal couplings (STC). Thanks to the work carried out by a few groups in the last decade, measurement techniques and devices are now available to fully determine the field E(x,y,t) in such cases. Furthermore, there are now several striking examples of how to take benefit of carefully controlled STC to finely control laser-matter interaction processes, especially at ultrahigh laser intensities and down to the attosecond time scale. This series of tutorial will provide an accessible introduction to STC, their metrology and a few selected examples of their applications.

Dátum: 2024. március 1.

Előadás címe: Introduction to spatio-temporal couplings of ultrashort lasers: metrology and applications: Basics of spatio-temporal couplings

Előadó: Fabien Quéré


The accurate temporal characterization of ultrashort laser pulses has now become a routine procedure in all labs working with femtosecond lasers, providing the complex field E(t) of these pulses, and such measurements have become a key tool for the optimization and control of laser-matter interaction experiments. Yet, they are actually insufficient to fully characterize an ultrashort laser beam, which is intrinsically a 3D physical object, described by a  complex field E(x,y,t), where x and y are the spatial coordinates transverse to the propagation direction. In many cases of interest, the spatial and temporal dependences of this field cannot be separated: in such instances the beam is said to exhibit spatio-temporal couplings (STC). Thanks to the work carried out by a few groups in the last decade, measurement techniques and devices are now available to fully determine the field E(x,y,t) in such cases. Furthermore, there are now several striking examples of how to take benefit of carefully controlled STC to finely control laser-matter interaction processes, especially at ultrahigh laser intensities and down to the attosecond time scale. This series of tutorial will provide an accessible introduction to STC, their metrology and a few selected examples of their applications.

Dátum: 2023. november 30.

Előadás címe: Nobel Prize 2023; the physics of attosecond pulses

Előadó: Katalin Varjú and Péter Dombi (ELI ALPS)


The 2023 Nobel Prize in Physics is for the study of the movement of electrons in atoms, molecules and matter in the condensed phase by means of attosecond spectroscopy. In this talk we will review the history - via science advancements - of the evolution of this research field, that led to the birth of attoscience, and will describe some applications of the field in the recent years. We will also give a brief summary of the relevance of this Prize for ELI ALPS. We both had the pleasure of working and publishing with the Laureates, so we can add personal flavour to introducing this topic.

Dátum: 2023. október 27.

Előadás címe: Nanostructures: From basics to practical applications

Előadó: Zoltán Erdélyi


In this presentation, my aim is to show a repertoire of our activities. Thus, the presentation will not focus on a single topic, but will bring examples from several areas that may seem distant at first sight. However, there is at least one link among them. The most obvious link is that nanostructures play a major role in each case. In presenting the topics, I will try to find a balance between making it clear to nonexperts in the field why we have done what we have done, what is of significance, from which they might draw ideas, while at the same time not being superficial to those more familiar with the topics. I intend to address the following topics:

Temperature-induced processes in thin films, multilayers, nanorods, solid and porous nanospheres: morphological changes, solid-state reaction, phase diagrams of nanosystems

Applications: plasmonic properties of metal oxide-porous Au hybrid nanoparticles, gas (e.g. CO2, H2) and vapour permeability of membranes (metal oxide, resin, polymer), optical and electrical properties of nanolaminates, photocatalysis

Dátum: 2023. szeptember 8.

Előadás címe: From inertial confinement fusion to inertial fusion energy

Előadó: István B. Földes


50 years of efforts to prove the feasibility of nuclear fusion using inertial fusion resulted in scientific breakeven on the 5th December 2022, when more fusion energy was generated, than the energy of the used laser beams. In this talk the requirements and the physics of laser fusion are summarized, and details of the experiments of the scientific breakeven are given. On the other hand, as it will be shown, this result is still far from producing usable energy with this method. Possibilities of developments from inertial confinement fusion (ICF) toward inertial fusion energy (IFE), i.e. for energy production are considered. New European and increasing private efforts into this direction should accelerate development.

Dátum: 2023. szeptember 7.

Előadás címe: Electromagnetic mass formulas for the X17 and E38 particles derived from quantized Volkov states

Előadó: Sándor Varró


Recent observations of anomalous angular correlations of electron-positron pairs in several nuclear reactions have indicated the existence of a hypothetical neutral boson of rest mass ~17 MeV/c^2, called the X17 particle [1, 1b, 1c]. A similar idea may help in interpreting the other set of experiments on photon pair spectra around the invariant mass ~38 MeV/c^2, by assuming the existence of the so-called E38 particle [2]. Besides a fifth force explanation of the ATOMKI nuclear anomalies [3], the QED meson theory due to Wong [4, 4b] may reproduce quite well the above-mentioned invariant masses.

In the present talk we base our considerations on the exact solutions of the Dirac equation of the system „charged particle + a quantized electromagnetic plane wave”, which has long been used in the quantum description of high-harmonic generation in mutiphoton Compton scattering [5, 5b]. We will show that these non-perturbative solutions, applied to the proton, lead to a mass term for the dressed radiation with the value (rest mass)c^2 = 17.0087 MeV [5c]. This may perhaps be identified with the X17 vector boson resonace, found by the ATOMKI scientists in several experiments [1, 1b, 1c]. A similar considerations with the udd quarks of the neutron yields the value (rest mass)c^2 = 37.9938 MeV, which may correspond to the hypotetical E38 particle [2]. We emphasize that, besides the Sommerfeld fine structure constant and the proton (neutron) mass, our derived formulas contain merely some statistical factors, so they do not contain any adjustable parameters, like e.g. the flux tube radius in Wong’s formalism [4b]. One of the motivations for giving the present talk has been to illustrate the synergy of applying non-perturbative strong-field and quantum optics methods, for possible interpretations of some particle physics phenomena, being in the frontiers of recent interests.



[1] Krasznahorkay A J, Csatlós M, Csige L, Gácsi Z, Gulyás J, Hunyadi M, Kuti I, Nyakó B M, Stuhl L, Timár J, Tornyi T G, Vajta Zs, Ketel T J and Krasznahorkay A, Observation of anomalous internal pair creation in 8Be : a possible indication of a light, neutral boson. Phys. Rev. Lett. 116, 042501 (2016). [1b] Krasznahorkay A J, et al., New anomaly observed in 12C supports the existence and the vector character of the hypothetical X17 boson. Phys. Rev. C 106,  L061601 (2022). [1c] Krasznahorkay A J, Krasznahorkay A, Csatlós M, Csige L and Timár J, A new particle is being born in ATOMKI that could make a connection to dark matter. Nucl. Phys. News 32 (2), 10-15 (2022).

[2] Abraamyan K, Austin C, Baznat M, Gudima K, Kozhin M, Reznikov S and Sorin A, Check of the structure in photon pairs spectra at the invariant mass of about 38 MeV/c^2. EJP Web of Conferences 204, 08004 (2019).

[3] Feng J L, Tait T M P and Verhaaren Ch B, Dynamical evidence for a fifth force explanation of the ATOMKI nuclear anomalies. Phys. Rev. D 102,  036016 (2020).

[4] Wong Ch-Y, Open string QED meson decription of the X17 particle and dark matter. JHEP08, 165 (2022). [4b] Wong Ch-Y,  QED meson description of the anomalous particles and the X17 particle. ISMD 2023 - 52nd Intl. Symp. on Multiparticle Dynamics, Aug 21-25 2023 - Gyöngyös, Hungary.

[5] Varró S, Theoretical study of the interaction of free electrons with intense light. (Ph.D. dissertation, 1981). Hung. Phys. Journal XXXI, 399-454 (1983).  [5b] Bergou J and Varró S, Nonlinear scattering processes in the presence of a quantised radiation field: II. Relativistic treatment. J. Phys. A: Math. Gen. 14, 2281-2303 (1981). [5c] Varró S, Proposal for an electromagnetic mass formula for the X17 particle. Talk presented at ISMD 2023 - 52nd Intl. Symp. on Multiparticle Dynamics, August 21-25 2023 - Gyöngyös, Hungary.

Dátum: 2023. június 30.

Előadás címe: Proposals for particle acceleration in plasma at high repetition rate using few-cycle laser pulses

Előadó: Zsolt Lécz (ELI ALPS Részecskegyorsítási csoport)


Since the invention of laser wakefields, generated by high intensity, femtosecond pulses in gaseous targets, the electron acceleration in dilute plasmas has been investigated both theoretically and experimentally. This scheme looks extremely promising to partially replace the conventional accelerators and to generate high quality relativistic electron bunches reaching several GeV maximum energies. However, in the case of ultrashort pulses new physical effects emerge, which are not yet fully understood, or not explored in the literature. Since the propagation of ultrashort laser pulses in plasma is highly nonlinear, it is necessary to model the interaction by means of numerical simulations. With the help of such (particle-in-cell) simulations I studied the electron acceleration process driven by very short (few-cycle) pulses and identified several negative effects which are not so important (or not present) in the case of longer pulses. Based on the knowledge acquired in the last two years I designed a three-component target, which is suitable for very efficient electron acceleration and allows for high energy gain within 2-millimeter distance. In my talk I will present the theoretical description of the short-pulse propagation in the proposed millimeter-long, three-stage target and I will show that, theoretically, GeV-class electron bunches can be accelerated by a half-Joule laser pulse in this new scheme.

In the second part of my talk, I will briefly discuss the possibility of proton (or deuteron) acceleration from high density gas jets using ~ 100 mJ laser pulses, which is highly relevant to the SYLOS-2 laser installed at ELI ALPS. I will present a realistic 3D simulation which indicates that 1 MeV mono-energetic proton bunch can be generated by such ultra-short laser pulses at ~kHz repetition rate.

Dátum: 2023. június 30.

Előadás címe: Numerical representation of tightly focused ultra-short laser pulses with different beam modes

Előadó: Szilárd Majorosi (ELI ALPS Részecskegyorsítási csoport)


Recent progresses in development of broad-band laser systems lead to the stable production of nearly single-cycle pulses at high repetition rates which then require tight focusing optics in order to reach highly relativistic intensities, needed for laser-plasma experiments. Most of the laser-driven particle acceleration schemes rely on particle-in-cell simulations where the laser pulses are usually initialized with Gaussian transverse profiles, employing the paraxial approximation at the beginning of the interaction. For tightly focused ultrashort pulses, however, a more accurate description is needed, otherwise the arising numerical artifacts may detrimentally affect the simulation outcome.

We present a general analytical-numerical framework going beyond the paraxial description for the laser electric and magnetic fields valid up to the near single-cycle pulse durations and focused beam spot sizes. We introduce corrections regarding spatial-temporal coupling, and corrections for the vector components of the electric- and magnetic-fields that could give precise initial fields for existing Maxwell-solvers ready to be used in particle-in-cell simulations. We combine this framework with beams based on the multimodal decomposition on the real Laguerre-Gaussian mode basis, to model pulses that have - more realistic- high order super-Gaussian profiles away from the focus in the same way.

Dátum: 2023. június 16.

Előadás címe: Chiral molecules in strong laser fields

Előadó: Debobrata Rajak (ELI ALPS SYLOS Gáz attoforrások csoport)


Light induced chemical processes are mediated by electronic interactions, which happens from atto-femto-pico second timescales, and are sensitive to the molecular structure. With advances in femto-second laser technology it has become possible to reach electric field values similar to the atomic/molecular binding potential. When an atom/molecule is exposed to such intense electromagnetic fields the potential barrier of the atom/molecule is considerably modified by the electromagnetic field. This modification is a dynamical process (see Fig 1.), occurring as the electromagnetic field oscillates, i.e. on the attosecond timescale (it takes only ~667 as for a visible electric field to go from its peak to zero). At the maximum of the laser field (Fig 1. a), the molecular potential barrier is lowered significantly and the electrons can tunnel out of this reduced barrier into the continuum (Fig 1. a 1). These tunnelled electrons are then driven by the oscillating laser field and can follow different trajectories (Fig 1. a 2). Some of them can be driven back to the ionic core, leading to a variety of processes: re-scattering, or recombination back to the ion emitting an XUV photon, or even diffraction from the molecular potential itself (Fig 1. b). These phenomena, referred to as “self-imaging”, enable measuring structural and dynamics information with unprecedented resolutions – Angströms and attoseconds. However, as the complexity of the target increases, deciphering the information becomes more difficult, such that the majority of self-imaging measurements have up to now been restricted to small systems (diatomics, triatomics).

In this work, we investigate the sensitivity of self-imaging to molecular chirality. We measure the 3D photoelectron angular distributions resulting from the photoionization of fenchone and alpha-pinene molecules by a strong infrared laser field. When the field is circularly polarized, the electron distribution is asymmetric relative to the laser propagation axis: more electrons are ejected forward or backward, depending on the handedness of the molecule and the incident light. This chiroptical process, called Photo-Electron Circular Dichroism, is a pure electric dipole effect, leading to asymmetries in the few % range. When we switch the polarization state to elliptical, we observe the emergence of much higher energy electrons, which have been driven back towards their parent ion by the laser field before diffracting on the potential. We observe a strong forward-backward asymmetry in these diffracted electrons, and we show that this chiral laser-induced electron diffraction is very sensitive to the molecular structure. Last, we switch to linearly polarized laser pulses, and measure a chirosensitive rotation of the photoelectron angular distribution around the light propagation direction. This effect is interpreted as the result of the action of the laser magnetic field on the electron trajectories.




Figure 1. Dynamical processes involved in strong-field ionization: a) At peak electric field the electrons tunnels out of the modified potential barrier, b) when the electric field reverses sign in the next half cycle these electrons maybe driven back to ionic core leading to re-scattering, recombination or diffraction.

Dátum: 2023. június 15.

Előadás címe: From the figure-8 motion to the high-intensity Compton effect

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


We discuss the exact relativistic description of both the classical and the quantum mechanical motion of charged particles interacting with a laser field of arbitrary intensity. This subject gives us also a good opportunity to celebrate the centenary of Compton’s discovery [1], which is an important ingredient of quantum electrodynamics (QED). First, in a brief historical overview we shall highlight the wave-particle duality and simultaneity in Compton scattering [2], [3].

The exact solutions of the Lorentz and Dirac equations of a charged particle in a plane electromagnetic wave in vacuum are represented by the well-known figure-8 motion and the Volkov states, respectively. These solutions have been extensively used in describing high-harmonic emission and attosecond pulse generation in the Compton or Thomson scattering processes [4]. They also have a role in the physics of free electron lasers [5]. Here we point out the surprising mathematical connection between the relativistic figure-8 motion in a monochromatic radiation and the classical Kepler-Coulomb trajectories in a central field [6].

By going beyond the external field approximation, the Dirac (Klein-Gordon or Schrödinger) equation of the joint system of a charged particle interacting with quantized radiation modes in vacuum can also be solved exactly in various cases [7], [8]. The photon part of the single-mode stationary states are squeezed (coherent) number states. The photon statistics has been determined quite recently in terms of Gegenbauer polynomials [9], and this is now used for a refined analysis of high-harmonic generation in a quantized radiation field, which was first studied long ago [7].

Finally we discuss the interaction of a charged Dirac particle with two co-propagating circularly polarized quantized modes. On the basis of the recently found exact solutions, we shall see that entangled photon pairs naturally appear in this system, like in the quantum optical non-degenerate parametric down-conversion process. In a special case the probability amplitudes of the distribution of these photon pairs reduce to Zernike functions, which are well-kown in the theory of aberration in classical optical imaging. Accordingly, it is justified to introduce the concepts of aberration and Zernike moments on quantum phase space, which may give a new aspect in the theoretical study of high-order QED and parametric processes in laser-matter interactions.



[1] Compton A H 1922 The spectrum of secondary X-rays. Phys. Rev. 19, 267-268 (1922).

[2] Compton A H and Simon A W 1925 Directed quanta of scattered X-rays. Phys. Rev. 26, 289-299 (1925).

[3] Bay Z, Henri V P and Mc Lernon F 1955 Simultaneity in the Compton effect. Phys. Rev. 97, 1710-1712 (1955).

[4] Hack Sz, Varró S and Czirják A 2018 Carrier-envelope phase controlled isolated attosecond pulses in the nm wavelength range, based on coherent nonlinear Thomson back-scattering. New Journal of Physics 20, 073043 (2018).

[5] Varró S 2012 (Ed.) Free Electron Lasers.  (Rijeka, InTech, 2012).

[6] Varró S 2010 Intensity effects and absolute phase effects in nonlinear laser-matter interactions. In Laser Pulse Phenomena and Applications. (Duarte F J (Ed.); Rijeka, InTech, 2010). Chapter 12.

[7] Bergou J and Varró 1981 Nonlinear scattering processes in the presence of a quantised radiation field: II. Relativistic treatment. Journal of Physics A: Math. Gen. 14, 2281-2303 (1981).

[8] Varró S 2021 Quantum optical aspects of high-harmonic generation. Photonics 8, 269 (2021).         

[9] Varró S 2022 Coherent and incoherent superposition of transition matrix elements of the squeezing operator. New Journal of Physics 24, 053035 (2022).


Dátum: 2023. május 5.

Előadás címe: The U.S. science funding landscape: NSF and sister federal funding agencies

Előadó: Vyacheslav (Slava) Lukin (programigazgató, National Science Foundation, USA)


This seminar will provide a general overview of the U.S. federal science funding landscape with a focus on physical sciences.  The U.S. federal science funding is allocated by the U.S. Congress via several federal agencies, including the National Science Foundation, the Department of Energy, the National Institute of Health, the National Aeronautics and Space Administration, and many others.  It is a uniquely complex system where federal agencies responsible for support of fundamental research interact with the applied mission-focused agencies that pursue specific societal, technological, and/or national security goals.  I will provide an in-depth look into the functioning of my own agency, the National Science Foundation, and will use the field of plasma science and engineering as a prime example of a research field where inter-agency and international cooperation play an essential role in the science funding landscape.

Dátum: 2023. április 27.

Előadás címe: Functional Nanoengineering: Materials for the Future





9:30 – 9:40         Gábor Szabó (ELI ALPS) - Welcome notes


9:40 – 10:30       Pulickel M. Ajayan (Rice University) - Materials Design through NanoEngineering


The last two decades in engineering sciences have been dominated by spectacular discoveries in nanotechnology. This talk will focus on some of these developments and in particular the challenges and opportunities in designing and synthesizing functional nanoengineered materials. The talk will discuss several classes of materials, for example, carbon-based nanostructures and two-dimensional structures, and the impact of bottom-up engineering on the design of material systems relevant to many areas of applications including energy, structural, chemical, and electronics. Several aspects that include synthesis, processing and manufacturing of materials will be broadly discussed to convey the goals of achieving functional nanoengineered materials.


10:30 – 11:20    Róbert Vajtai (Rice University) - sp2 to sp3 Materials for Ultrawide- Bandgap Electronics


State-of-the-art electronics is one of the driving forces in materials development. While the development of the most widely appreciated new materials target mini(nano)aturization and low energy dissipation, some applications request development in the opposite direction: developing devices for high-power and high-frequency electronics. In this talk, I summarize the properties of the most important UWBG materials and talk about our work on the growth and characterization of diamond and boron nitride for applications in advanced electronics.


11:20 – 12:10    Levente Tapasztó (Centre for Energy Research) - Engineering the Properties of 2D TMC Crystals by Structural Modifications down to Atomic Level


Transition metal chalcogenides (TMCs) are among the most widely studied two-dimensional (2D) materials, second only to graphene. In this talk, I will discuss our various contributions to the field of 2D TMC materials: their large-area exfoliation, revealing their intrinsic defect structure, and how it affects the electronic structure, strain engineering of their band gap, as well as their atomic-level structural modification for engineering their properties.


12:10 – 13:00    Katalin Varjú (ELI ALPS) - Commissioning Progress and User Access at the ELI ALPS Research Institute


The primary mission of the ELI ALPS research facility in Szeged, Hungary is to provide laser and secondary light and particle sources in the form of ultrashort bursts with high repetition rates. Energetic coherent light pulses of few optical cycles are available from the terahertz (1012 Hz) to the X-ray (1018 — 1019 Hz) frequency range. ELI ALPS will be dedicated to study extremely fast dynamics by taking snapshots in the attosecond scale of the electron dynamics in atoms, molecules, plasmas and solids. The parallel existence of these secondary sources and state of the art lasers including PW-class lasers within the same facility, offers unique time-resolved investigation possibilities for both nonrelativistic and relativistic interaction of light with all the four phases of matter. ELI ALPS will also pursue research with ultrahigh intensity lasers.

The constructed buildings house the laser equipment, secondary sources, target areas, laser preparation and other special laboratories, including 4.000m2 of clean rooms. It also provides sufficient administration space for approximately 250 researchers and support staff. There are seminar, meeting and conference rooms. There are also electrical, mechanical and optical workshops. These state-of-the-art facilities require specialised engineering design and cutting-edge implementation of the latest technology for vibration levels, thermal stability, relative humidity, clean room facilities and radiation protection conditions. The ELI-ALPS is approaching the end of the construction phase for the main priority being the installation and commissioning of the remaining research technology.

Dátum: 2023. március 17.

Előadás címe: Critical problems for semiconductors in the hyperscale and AI era of computing

Előadó: Zane Ball (a Data Center Platform Engineering and Architecture (Intel Corporation) alelnöke és vezérigazgatója)


Dátum: 2023. március 10.

Előadás címe: Bridging the gap between industry and academia

Előadó: Prof. Michael Kaschke


Dátum: 2023. március 9.

Előadás címe: Quantum aberration in the phase space of entangled photons

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


In the first part of the talk we attempt to give a brief exposition of the scientific background of the subject we are discussing. The following points will be highlighted: The coherent and squeezed states of a quantum-mechanical harmonic oscillator (which may also represent a photon mode of the electromagnetic radiation) have already been  known immediately after the invention of wave mechanics. Not much later, in 1935, Schrödinger introduced the concept of entanglement (“Verschränkung”), when the quanta are distributed coherently among several degrees of freedom. His analysis was motivated by the critics due to Einstein, Podolsky and Rosen (EPR, 1935), of the quantum description, in general. The experimental investigations of such fundamental questions became possible after the invention of the laser. From the sixthies of the last century the quantum states of light have played an important role in the theory and practice of lasers and parametric processes in quantum optics and quantum imaging [1], [2], [3]. The study and application of entanglement have become one of the main ingredients of quantum information science [4]. The non-classical states also naturally appear in the non-perturbative description of the minimal coupling interaction of radiation fields with charges, e.g. in the non-linear Compton process or in high-order harmonic generation [5], [6], [7], so they have a role in attosecond physics, too. 

Recently we have derived the probability amplitudes of general squeezing transitions, in terms of Gegenbauer polynomials [8]. On the basis of this result we have also determined the photon statistics of thermal noise (black-body radiation) amplification in a degenerate parametric amplifier. In the meantime we have applied an analogous mathematical procedure for the non-degenerate process producing EPR-type entangled photon pairs. In the second half of the talk we shall discuss the results of the latter study. The photon statistics of the entangled photon pairs have been calculated, in a close connection with the quantum phase formalism, which we have already introduced earlier [9]. It will be shown that in a special case, the derived probability amplitudes reduce to the Zernike functions (polynomials), well-kown in the classical theory of aberration in optical imaging. The quantum Zernike polynomials depend on the phase-space variables, and they form a complete set of orthogonal aberration functions. Thanks to these results, it is possible to quantitatively assess the parametric photon sources, for example, in terms of the corresponding Zernike moments. 



[1] Lugiato L A, Gatti A and Brambilla E, Quantum imaging. J. Opt. B: Quantum Semiclass. Opt. 4 (2002) S176–S183.

[2] Dodonov V V, Nonclassical states in quantum optics: a squeezed review of the first 75 years. J. Opt. B: Quantum Semiclass. Opt. 4,R1–R33 (2002). 

[3] Andersen U L et al, 30 years of squeezed light generation. Phys. Scr. 91, 053001 (2016). 

[4] > The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics 2022 to Alain Aspect, John F. Clauser and Anton Zeilinger; “for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science”.  <

[5] Varró S : Entangled photon-electron states and the number-phase minimum uncertainty states of the photon field. New Journal of Physics 10, 053028 (2008)

[6] Varró S : Entangled states and entropy remnants of a photon-electron system. Physica Scripta T140, 014038 (2010).

[7] Varró S, Quantum optical aspects of high-harmonic generation. Photonics 2021, 8, 269 (2021).  

[8] Varró S, Coherent and incoherent superposition of transition matrix elements of the squeezing operator. New Journal of Physics 24, 053035 (2022). 

[9] Varró S : Regular phase operator and SU(1,1) coherent states of the harmonic oscillator. Physica Scripta 90 (7) 074053 (2015).

Dátum: 2023. február 7.

Előadás címe: Visualizing Electron Dynamics at Interfaces Using XUV Light

Előadó: L. Robert Baker


Directly observing electron dynamics at surfaces is required to understand and control the material properties that determine efficiency of many applications including efficient energy conversion as well as ultrafast information processing.  Toward this goal, we have developed extreme ultraviolet reflection-absorption (XUV-RA) spectroscopy as a surface-specific analog of XUV transient absorption.  This method combines the benefits of traditional X-ray absorption spectroscopy, such as element, oxidation, and spin state resolution, with surface sensitivity and ultrafast time resolution.  Using this technique, we investigate charge and spin dynamics in materials with applications ranging from photocatalysis to optical control of magnetic switching.  In one example, we describe a systematic comparison of surface and bulk electron polaron formation in hematite showing that surface self-trapping dynamics differ significantly from bulk and that these dynamics can be systematically tuned by surface molecular functionalization offering the possibility for design of photocatalytic interfaces with enhanced carrier transport based on earth abundant materials.  In a second example, we highlight evolving applications of XUV-RA spectroscopy to study spin dynamics at surfaces.  Applications include understanding ultrafast spin crossover in magnetic semiconductors as well as control of spin polarized electron dynamics at chiral photochemical interfaces.  Last, I will describe capabilities that will soon become available at the NSF National eXtreme Ultrafast Science Facility (NeXUS) that is currently under development at Ohio State University.

Dátum: 2022. november 18.

Előadás címe: Calculations of molecular photoabsorbtion for astrophysics and other purposes

Előadó: Jonathan Tennyson


Spectroscopy provides our main window on the Universe about us. The detection of many exoplanets orbiting nearby stars has led to the desire to characterize these planets by looking at their spectra. The ERC-funded ExoMol project which I lead provides the  spectroscopic data needed for this activity; given that many of the observed planets are hot these datasets are huge. The seminar will discuss how we compute spectroscopic line lists and the extension of the methodology to photodissociation, and the use of these data in both astrophysical and terrestrial applications. Procedures to compute photodissociation spectra will also be outlined.

Dátum: 2022. november 4.

Előadás címe: 9th Users' Workshop



In the framework of the established series of Users’ Workshops the Extreme Light Infrastructure – Attosecond Light Pulse Source (ELI ALPS)  is organizing its ninth User Workshop on November 3 and 4, 2022. This year the Users’ Workshop is organized as an ELI ERIC ( joint event.

Dátum: 2022. november 3.

Előadás címe: 9th Users' Workshop

Előadó: ELI ALPS


In the framework of the established series of Users’ Workshops the Extreme Light Infrastructure – Attosecond Light Pulse Source (ELI ALPS)  is organizing its ninth User Workshop on November 3 and 4, 2022. This year the Users’ Workshop is organized as an ELI ERIC ( joint event.

Dátum: 2022. október 18.

Előadás címe: Researches on Laser Ion Acceleration and Laser Driven Neutron Source for Nuclear Resonance Analysis at ILE Osaka University

Előadó: Kunioki Mima


I start with brief introduction of the present status of Institute Laser Engineering (ILE) of Osaka University. Then, the topics on Laser Driven Ion Acceleration (LDIA) and Laser Driven Neutron Source (LDNS) researches at ILE are presented. Since early 1990’s, various schemes of LDIA are investigated as one of the applications of the intense short-pulse-laser interaction with plasmas [1]. The LDIA has been applied for radiography, medical application, neutron source and so on. In this seminar, I overview the researches at ILE Osaka Univ. on LDIA, laser driven neutron source (LDNS) [2]and its application to nuclear resonance absorption (NRA) [3] .

The LDNS is unique because the number of neutrons per micro pulse is very large and the source size and the pulse width are small. Therefore, the extensive research and development of LDNS are going on in the world. A scheme of LDNS (Pitcher- catcher) by the LDIA is described, which is the Pitcher-Catcher Scheme (PCS). The characteristics of the LDNS by PCS are compared with those of the accelerator driven neutron source (ADNS). Then, I explain a unique application of LDNS such as the nuclear resonance absorption (NRA) imaging. Namely, by the LDNS, the NRA imaging is possible with a relatively short beam line in comparison with that of the ADNS, since the neutron pulse width and the source size of LDNS are small. The future prospect of the R&D of the NRA imaging with LDNS [4] is also discussed.

[1] A. Macchi, P.59-P.92, Chap.5 Laser Driven Ion Acceleration, “Application of Laser-Driven Particle Acceleration”, Edited by P.R. Bolton, K. Parodi, and J. Schreiber, CRC press, Taylor &  Francis Group, 2018, (M. Borghesi will present this topic on LDIA in this seminar.)

[2] Lancaster, K.L., Karsch, S., Habara, H., et al., Characterization of 7Li(p,n)7Be neutron yields from laser produced ion beams for fast neutron radiography, Physics of Plasmas, 11.3404(2004)

[3] S. Kar, A. Green, H. Ahmed, A. Alejo, A.P.L. Robinson, M. Cerchez, R. Clarke, D. Doria, S. Dorkings, J. Fernandez, S.R. Mirfayzi1, P. McKenna5, K. Naughton1, D. Neely2, P. Norreys2,6, C. Peth3, H. Powell, J. A. Ruiz, J. Swain, O. Willi and M. Borghesi, “Beamed neutron emission driven by laser accelerated light ions” New J. Phys. 18, 053002 (2016).

[4] A.Yogo, et al., “Laser-driven neutron generation realizing single-shot resonance Spectroscopy”, to be published in PRX, 2022.

Dátum: 2022. október 14.

Előadás címe: Digital noise, and entropy as Hausdorff fractional dimension

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


In our earlier studies [1-3] we have shown that the Planck-Bose distribution of black-body radiation can be derived from the exponential  distribution, by splitting the continuous random energy into its integer and fractional part [3]. The binary digits (0 and 1) of the fractional part (which may also be considered as a sort of rounding-off error in energy measurements) inherit the randomness, and they are independent random variables [4]. According to our recent investigations, the variance of the  fractional part is the sum of particle-like and a wave-like fluctuations [1-2]. In the first part of the talk we discuss some features of the associated ‘particles’ which may be called ‘dark quanta’ or ‘grey photons’, since at large temperatures their energy is 2kT, where k is the Boltzmann constant and T is the absolute temperature. 

In the second part of the talk we shall discuss the statistics of a two-level system being in thermal equilibrium with the black-body radiation. By associating the numbers 0 and 1 to the ground state and to the excited state, respectively, the outcomes of a series of measurements of the population can be mapped to the continuum of numbers (like x = 0.10010110010...) of the unit interval. The relative frequencies of digits 0 and 1 tend to the corresponding probabilities, namely to 1 – b and b, respectively, where b is the Boltzmann factor of the upper state.  If b = 1/2, then the points corresponding to the realizations in the measurements visit the whole unit interval, except for a set of (Lebesgue) measure zero. In order to compare the sizes of sets of measure zero, the use of Hausdorff fractional dimensions has first been worked out by Besicovitch [5], and generalized later by others. By applying the mathematical results in [5], it turns out that the entropy of the two-level system is k(log2) times the Hausdorff fractional dimension d of the set of average populations in the unit interval. For instance,  in cases of b=1/2 and b=1/5 we have d=1 and d=0.721928, respectively. The Planck entropy of the corresponding spectral component of the black-body radiation can also be expressed by the Hausdorff dimension [6]. Our results contribute to the mathematics of digital processing measurement results, and may also be useful in describing some physical systems generating random numbers. 

[1] Varró S, Einstein's fluctuation formula. A historical overview. Fluctuation and Noise Letters, 6, R11-R46 (2006). arXiv: quant-ph/0611023 . 

[2] Varró S, A study on black-body radiation: classical and binary photons. Acta Physica Hungarica B 26, 365-389 (2006). arXiv: quant-ph/0611010 .

[3] Varró S, Irreducible decomposition of Gaussian distributions and the spectrum of black-body radiation. Physica Scripta 75, 160-169 (2007). arXiv: quant-ph/0610184 . 

[4] Varró S, The digital randomness of black-body radiation. Journal of Physics Conference Series 414, 012041 (2013). arXiv:1301.1997 [quant-ph] .

[5] Besicovitch A S, On the sum of digits of real numbers represented in the dyadic system. (On sets of fractional dimensions II.) Mathematische Annalen 110, 321-330 (1935). 

[6] Varró S, Planck entropy expressed by the Hausdorff dimension of the set of average excitation degrees of a two-level atom in thermal equilibrium. Talk S7.4.1.  presented at LPHYS’18  [27th International Laser Physics Workshop, 16-20 July 2018., Nottingham, UK]

Dátum: 2022. március 22.

Előadás címe: OPTOMAN – optics for big & scary fs/ps lasers

Előadó: Artūras Samalius


OPTOMAN will present latest developments in IBS coatings for extreme applications – new type of mirrors without discoloration for ultrafast laser applications, mirrors for multi-pass cell applications. New developments in UV and mid-IR ranges.

Dátum: 2022. március 18.

Előadás címe: Multiphoton processes in the field of a ‘pedestal’

Előadó: Varró Sándor (ELI ALPS Elméleti és szimulációs csoport)


The high-intensity light pulses used in mutiphoton experiments come from amplifiers, and these pulses contain quite strong (unwanted) pre-pulses, or ‘pedestals’. The main source of the pedestal is said to be the amplified spontaneous emission (ASE) of the amplifying medium. Since the photon statistics of the ASE is different from that of the main pulse, the study of multiphoton processes taking place in a pedestal may be interesting, both in theory and in experiments. This is even so, because in the last couple of years there has been a growing activity in investigating how, and to what extent the quantum nature of light manifest itself in strong-field laser-matter interactions? It seems that quantum optical considerations will receive an increasing importance in the interpretation of certain experimental results on high-order processes, like quantum correlations and photon counting measurements [1-5]. 

Recently we have worked out a general quantum optical theory of multiphoton processes [6], which seems to be capable of answering the above question in several cases. In the present talk we shall briefly explain the main ingredients of this theory, and deal with the possible role of photon statistics in high-harmonic generation. 

On the basis of this general theory [6], and with the help of our new results on squeezing transitions [7], we have also calculated the transition probabilities of electron excitation and scattering in the field of a ‘pedestal’. The larger part of the talk will be devoted to the discussion of the main characteristics of such multiphoton processes. 



[1] Tsatrafyllis N, Kühn S, Dumergue M, Földi P, Kahaly S, Cormier E, Gonoskov I A, Kiss B, Varjú K, Varró S and Tzallas P, Sub-cycle quantum electrodynamics in strongly laser-driven semiconductors. Physical Review Letters 122, 193602 (2019).

[2] Gorlach, A.; Neufeld, O.; Rivera, N.; Cohen, O.; Kaminer, I. The quantum-optical nature of high harmonic generation. Nat. Commun. 2020, 11, 4598.

[3] Lewenstein, M.; Ciappina, M.F.; Pisanty, E.; Rivera-Dean, J.; Lamprou, T.; Tzallas, P. The quantum nature of light in high harmonic generation. (2020). arXiv: 2008.10221.

[4] Földi P, Magashegyi I, Gombkötő Á and Varró S, Describing high-order harmonic generation using quantum optical models. Photonics 2021, 8, 263. (2021).

[5] Gombkötő Á, Földi P, Varró S, A quantum optical description of photon statistics and cross-correlations in high harmonic generation. Physical Review A 104, 033703 (2021). 

[6] Varró S, Quantum optical aspects of high-harmonic generation. Photonics 8, 269 (2021) [ ]. 

[7] Varró S, Coherent and incoherent superposition of transition matrix elements of the squeezing operator.  Journal of Physics Conf. Ser. (2022). E-print: arXiv: 2112.08430 [quant-ph].

Dátum: 2022. február 4.

Előadás címe: Decoding the response of correlated electrons in methylated system to photo-ionization

Előadó: Kalyany Chordiya


A long awaiting dream for researchers in the field of chemistry, material science and biology is understanding of the ultrafast charge migration in molecular systems. The extracted information on charge migration dynamics, will ultimately assist in engineering of new materials for photo-voltaic applications, photo-responsive drugs, photo-catalysis, determining fragmentation channel and understand radiation damage or photo-protective response to radiation therapy. To move in this direction, using the single particle Green's function Non-dyson ADC(3) method [1], we study the influence of tautomeric sites and methyl group on the charge migration dynamics in Uracil and Thymine nucleobases. Our results manifest that, the charge migration dynamics can be influenced and tailored by the site of tautomeric hydrogen, presence of methyl group and by targeting highly correlated molecular orbitals. Tautomerisation is important for the biologically important systems as it is interpreted to be one of the photo-protective response mechanism to radiation [2], in living organisms. The analysis also reveal that the maximum flux time (within 100 as) i.e., time when atomic site starts to donate or receive electronic density, shows the influence of electronegativity of atoms in the molecular systems. Thus, present study could be utilized to understand the possible response to post-radiation, and could be of interest to design photo-responsive materials.

[1] J. Schirmer, A. B. Trofimov, and G. Stelter. J. Chem. Phys. 109.12 (1998), pp. 4734–4744.

[2] D. Lapotko, E. Lukianova, M. Potapnev, O. Aleinikova, A. Oraevsky, Cancer Lett., 239, (2006), pp. 36 - 45

Dátum: 2021. május 28.

Előadás címe: Quantum secrets of strong-field ionization: quantum interference and the non-zero tunnel exit momentum

Előadó: Hack Szabolcs, Czirják Attila


The problems of tunneling time and tunnel exit momentum in strong-field ionization are of outstanding importance regarding both quantum theory and attosecond metrology. Based on a phase space analysis and the relevant energy distribution, we reveal the importance of quantum interference between tunneling and over-the-barrier pathways of escape during the liberation of a single atomic electron by a linearly polarized laser pulse, which explains experimentally measured non-zero values of the tunnel exit momentum. We suggest and justify improved initial conditions for a classical particle approximation of strong-field ionization, based on the quantum momentum function, and we show how to reconstruct them from the detected momentum of an escaped electron.

Dátum: 2021. április 9.

Előadás címe: Electronic structure of two-dimensional hexagonal boron nitride on Au coated Rh(111) surface

Előadó: Halasi Gyula


Hexagonal boron nitride (h-BN) has attracted a vivid interest, partly because this material is a very good insulating support for graphene nanoelectronics (and is also a graphene analogue), only weakly influencing the properties of graphene. Due to the weak metal-nitride interaction, the h-BN monolayer is planar on the close-packed surfaces of coinage metals (Cu, Ag, Au). Thereby, between gold and h-BN it was not possible to grow a continuous monolayer of the BN before the onset of the second layer. On the other hand, the h-BN monolayer has a periodically corrugated structure on Rh(111), so-called ‘‘nanomesh’’ due to the lattice mismatch and the relatively strong interaction between h-BN and the metal. It has two specific regions, pores and wires depending on the layer distance from the surface. The nanomesh surface is a good template for metal nanoclusters and organic molecules. Since literature data about h-BN growth on alloys is very scarce, in the present study we prepared h-BN on gold-rhodium surface alloys with a different gold content (0, 0.95, 1.15, 1.8 monolayers). The central aim was to measure and analyze the valence band k-space region of these surfaces with the NanoESCA, using its internal light sources. The Au layer was prepared on the clean Rh(111) surface by metal evaporation and annealing (1050 K). Then hexagonal BN was synthetized on top, decomposing borazine (B3N3H6) at 1050 K. The formation of the nanomesh structure resulted in the splitting of the s and p bands of h-BN into various branches, and this phenomenon was influenced by the Au content. Interestingly, rhodium features were influenced by the presence of h-BN even in the energy range close to the Fermi level, where the insulating h-BN has no states: replicas of the original features appear on constant energy slices shifted by the superlattice reciprocal vector. With the help of X-ray photoelectron spectroscopy (XPS) we revealed the h-BN can act as a template not only for species adsorbed on top of it but also for the interfacing layer below it.

Dátum: 2021. március 26.

Előadás címe: Optical probing of plasmonic hot electron occupancies

Előadó: Budai Judit, Pápa Zsuzsanna


Hot electron generation upon the excitation of surface plasmon polaritons plays a key role in emerging applications such as photocatalysis, light harvesting and sensorics. In this seminar talk, we will discuss the time evolution and in depth distribution of such hot carriers. For this purpose, we demonstrate an experimental method to directly measure plasmon-associated changes in dielectric properties of metallic surfaces utilizing spectroscopic ellipsometry. Monitoring these changes in the dielectric function allows us to follow changes in the electron distribution. Pump-probe and continuous wave experiments revealed different aspects of plasmon generation. Pump-probe ellipsometric approach with <100 fs resolution enabled us to identify the different stages of plasmon decay through which electrons are scattered among each other and interact with the lattice. For continuous wave illumination, hot electrons are always present in the system, therefore the spectral signature of a hot electron population and its spatial location within the plasmonic thin film can be determined using the retrieved dielectric function from cw measurements.

Dátum: 2020. december 11.

Előadás címe: Notes on the stimulated emission of radiation; on the occasion of ‘LASER 60’

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


The study of the physical bases of stimulated emission and black-body radiation have been closely related from the very beginning. We feel it justified to devote some time for their joint analysis, in particular, in the present year, when we celebrate the 60th anniversary of the invention of the LASER (Light Amplification by Stimulated Emission of Radiation). Moreover, one should also keep in mind that in the course of his work on black-body radiation,  the elementary quantum of action h was discovered by Planck just 120 years ago. In the present talk, though we shall highlight some moments in the development of the laser during the past 60 years, but the emphasis shall be put on the fundamental aspects. Our purpose is twofold; on one hand we discuss some lesser known historical facts concerning the stimulated emission of radiation as appeared in the works of Planck (1911) and Einstein (1916). On the other hand, we present our recent results; the first of which is a new phenomenological derivation of the entropy of a Planckian oscillator. Concerning the probabilistic description,  we will show how to build up a correspondence between entropy and the fractal dimension of the relative frequencies of the excitation of a Bohr atom in thermal equilibrium.

Dátum: 2020. október 16.

Előadás címe: Scattering of light on a random rough surface; "per aspera ad astra"

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


Dátum: 2020. október 2.

Előadás címe: Attosecond correlation metrology as seeded free-electron lasers

Előadó: Giuseppe Sansone


Recently the generation of trains [1] and isolated[2] attosecond pulses was demonstrated at Free Electron Lasers (FELs) operating in the extreme ultraviolet (XUV) and soft X-ray spectral

range. FEL-driven attosecond sources present important advantages with respect to table-top

attosecond sources based on high-order harmonic generation, including high-energies per pulse (typically in the microjoule range), tunability of the photon energy and shaping capability (in the case of train of attosecond pulses). On the other hand, these sources present significant drawbacks such as temporal jitter between the XUV waveform and the optical/infrared laser and lowrepetition

rates. In this talk I will show how the control of the relative phase between the harmonics

achieved at FERMI [3] gives access to its characterization, by implementing a correlation-based analysis of the photoelectron spectra generated by the combination of the attosecond and infrared pulses. I will also present novel ideas on how to extend the correlation-analysis tools for extending attosecond metrology to situations in which sub-cycle synchronization between the attosecond waveform and the infrared field is not guaranteed.


[1] P. K. Maroju et al. Attosecond pulse shaping using a seeded free-electron Laser, Nature 578, 386-391 (2020).

[2] J. Duris et al. Tunable isolated attosecond X-ray pulses with gigawatt peak power from a free-electron laser, Nature Photon. 14, 30-36 (2020).

[3] K. C. Prince et al. Coherent control with a short-wavelength free-electron laser, Nature Photon. 10, 176-179 (2016).

Dátum: 2020. szeptember 24.

Előadás címe: Electromagnetic radiation from plasma dipole oscillation

Előadó: Min Sup Hur


Plasma oscillation is attractive as a radiation source, since the frequency can be easily controlled just by changing the plasma density and the amplitude can be made arbitrarily high (up to the wavebreaking limit) as there is no damage threshold in plasmas. Unfortunately it is never trivial to convert the electrostatic plasma oscillation to an electromagnetic wave. There are several physical reasons for that; for an instance, the plasma oscillation usually appears as a traveling wave (wakefield or Langmuir wave), which does not phase-match with the electromagnetic waves inside the plasma. With the aid of external magnetic field or non-uniformity of the plasma or linear and nonlinear scattering processes, the energy of the plasma wave can be partially converted to electromagnetic energy. Recently we reported a totally different approach to obtain an electromagnetic emission from the plasma oscillation. The idea is generating a localized bunch of electrons that oscillate in-phase, which we identify as a plasma dipole oscillator (PDO), by colliding two detuned laser pulses in plasma. From one-, two- and three-dimensional particle-in-cell (PIC) simulations, it is verified that the PDO oscillates at the local plasma frequency and emits a strong dipole radiation at the same frequency. The electrostatic-electromagnetic energy conversion does not require any complicated linear and nonlinear processes or external magnetic field. This property of the PDO makes it useful as a light source in the terahertz band (Kwon et al., Sci. Rep. 2018) and also as a novel diagnostic method for non-uniform plasma density (Kylychbekov et al., PSST 2020).  The PDO in a strongly magnetized plasma has even richer physics; diverse spectral modes such as upper-hybrid and R, L cutoffs of X-modes exist together, and the polarization of the radiation also changes with direction of the emission.  As the spectral density can be made high at a desired frequency, the PDO-THz can be potentially useful in THz electron acceleration, and other applications where narrowband THz is required. It is found that the PDO-emission and coherent cosmic radio bursts share several common features, making the PDO an interesting subject of lab-spacephysics or lab-astrophysics.

Dátum: 2020. július 2.

Előadás címe: OptoSigma Europe

Előadó: Mauro Persechino


Optosigma Europe -  part of the Optosigma Group - is specialised in manufacturing of optics, optomechanics and translation stages. The Company’s products include optics, optomechanics, manual and motorised stages, optical tables, fiber optics, light sources, laser analytics, and laser safety products. Standard and customised (shape, coatings, assembies, substrates, systems, etc) pruduct are available to find the best solution for the customer.

Dátum: 2020. június 17.

Előadás címe: Scientific Cameras and Inspection Systems

Előadó: Axel Wiegand


I.             Company facts

II.            Scientific CCD Cameras/ Sensor Basics

III.          Scientific cameras for NIR, VIS and UV applications

IV.          Scientific cameras for X-ray, EUV, and VUV applications

V.           New Sensor Technologies - Superresolution Cameras & sCMOS

VI.          greateyes inspection systems

Dátum: 2020. június 16.

Előadás címe: 5th Ws on Laser Based Transmutator



Georg Korn - Opening (2-5 mins)

Minister László Palkovics - Greetings (2-5 mins)

Gerard Mourou - Greetings (2-5 mins) 

Toshi Tajima - Summary of the Project (10 mins)

Karoly Osvay / Gabor Szabo  - Proton acceleration from ultrathin foils with 11 fs pulses – preliminary results (15 mins)

Allen Weeks - EU level initiative (10mins)

Georg Korn - Future Plan (10mins)

Dátum: 2020. április 20.

Előadás címe: Laser Components: High damage threshold IR optics Power and energy measurement

Előadó: Laser Components


Dátum: 2020. március 3.

Előadás címe: Femtosecond 100 W-level OPCPAs from near-IR to short-wave-IR wavelengths

Előadó: Robert Riedel


High power and high repetition rate lasers are critical for many applications in the physical, chemical, and biological sciences. Previously, laser sources from x-ray to THz were driven from Ti:Sapphire lasers at 800 nm with limited bandwidth (Fourier limited pulse of ~20 fs), and  more importantly limited power levels; power levels ~40 W and above require large complex cooling systems. Optical parametric chirped-pulse amplification (OPCPA) together with bulk crystal white-light-generation (WLG) opens up the possibility high power lasers (well above 100 W), with wavelength tunable and broadband (for example, < 10 fs at 800 nm), requiring no complex cooling with a compact design. Previous thermal studies of nonlinear crystals – BBO, LBO and KTA – demonstrated the possibility of using these crystals for high power applications at 800 nm and 1.5 µm. Recently, 100 W-level OPCPAs are now commercially available from Class 5 Photonics GmbH using BBO at 800 nm and KTA with a tunable range 1.45 – 2 µm.

Dátum: 2020. február 28.

Előadás címe: Femtosecond direct laser writing: a versatile tool in studying the microworld

Előadó: Gaszton Vizsnyiczai (Szegedi Biológiai Kutatóközpont)


Femtosecond direct laser writing, also known as two-photon polymerization, is a photolithographic method that enables the fabrication of 3D microstructures with submicron resolution. The possibility of creating arbitrary shaped 3D microstructures provides a general advantage for studying the physics and biology of the microworld in more detail. In this talk I will present experiments and applications relying on microstructures created with two-photon polymerization [1,2,3].

[1] Hydrodynamic synchronization of light driven microrotors, R Di Leonardo, A Búzás, L Kelemen, G Vizsnyiczai, L Oroszi, P Ormos, Physical review letters 109 (3), 034104

[2] Multiview microscopy of single cells through microstructure-based indirect optical manipulation, Vizsnyiczai, G., Búzás, A., Aekbote, B. L., Fekete, T., Grexa, I., Ormos, P., & Kelemen, L. (2020). Biomedical Optics Express, 11(2), 945-962.

[3] A transition to stable 1D swimming enhances E. coli motility through narrow channels, G Vizsnyiczai, G Frangipane, F Saglimbeni, S Bianchi, D Dell’Arciprete, and R Di Leonardo, Under review in Nature Communications.

Dátum: 2019. december 13.

Előadás címe: Draco laser driven protons and carbon ions from solid target

Előadó: Parvin Varmazyar


Nowadays, ion acceleration driven by super intense laser pulses is one of the most interesting fields of research because of potential applications such as cancer therapy, fast ignition, ion imagining etc. Intense laser pulses, due to possessing very strong electric and magnetic fields, are capable of accelerating ions to high energies over very short distances (the acceleration gradients obtained in plasmas are 100–1000 GeV/m, orders of magnitude higher than 10–100 MeV/m typical values of conventional accelerators), allowing for what is called as a tabletop ion accelerator. This paper is an experimental study of the interaction of the DRACO high power laser with solid targets. Since the temporal structure of the laser pulse affects the laser–matter interaction and change the condition of the main pulse interaction with the target, cleaning laser pulse and enhancing temporal laser contrast is necessary before starting experiment. Then, in the experiment, the intrinsic temporal contrast of the laser pulses was improved (two to three orders of magnitude) by using a re-collimating single plasma mirror before the pulses were focused onto thin plastic and gold foil targets under oblique incidence. Results show proton and carbon ions, accelerated in the target normal sheath acceleration (TNSA) regime. Origin of accelerating protons is contaminant  layers of water vapor or hydrocarbon behind the surface of target or oil. The highest proton cut-off energy was 32 MeV obtained from 95nm thin plastic targets and 25 MeV from 50 nm gold targets. Experimental evidence have not shown any heavy gold ions acceleration during experiment, which is due to screening effect of light ions acceleration.

Dátum: 2019. november 29.

Előadás címe: Coatings for high laser powers

Előadó: Artūras Samalius


OPTOMAN as a supplier for highly customized and application optimized IBS coated components will be introduced. Various coating technologies, advantages of IBS versus other available options. Having successfully collaborated with various research centers, such as DESY in Germany, HiLASE in Check Republic etc., there is hope to find common projects with ELI-ALPS as well.

Dátum: 2019. október 17.

Előadás címe: Intellectual Property - Basics

Előadó: Kürtössy Jenő


-              Research and Intellectual Property („IP”)

-              Why to protect IP ?

-              The case of Rubic’ s cube

-              Types of IP Publication of the scientific results or/and getting IP protection

-              What is a patent?

-              What can be patented? What cannot be patented?

-              General patentability criteria  (novelty, inventive step, industrial applicability)

-              Preventing the re-invention of the existing inventions (Patent Information the huge collection of technical and scientific knowledge)

Dátum: 2019. szeptember 9.

Előadás címe: Terahertz Devices based on metasurfaces

Előadó: Prof. Jianqiang Gu


Micrometer scale metasurfaces are widely explored as various devices and components serving the terahertz technology. Because of the excellent design flexibility, these metasurface based terahertz devices have uniques advantages and general design methodology, which continuously attracts researchers attention. This talk will present the series of terahertz metasurfaces designed to control the amplitude and phase of terahertz waves, which were conducted in Center for Terahertz Waves, Tianjin University.  These devices include terahertz lenses, modulators, cloak carpets and slow wave components based on plasmon induced transparency (PIT). In addition, recent results on metamaterial assisted photoconductive antennas will be discussed. 

Dátum: 2019. július 26.

Előadás címe: Laser-Plasma Physics and particle acceleration @ the Centro de Laseres Pulsados

Előadó: Luca Volpe


The Centro de Láseres Pulsados is a key Spanish User facility founded by the Ministry of Science, the region of Castilla y León and the University of Salamanca; it is included in the strategic Roadmap of Unique Scientific and Technical Infrastructures (ICTS) in Spain  and its main mission is to promote scientific and technological development by offering national and international user access.


The Uniqueness of CLPU is the multi Terawatt laser system VEGA composed by three independent and synchronised 30 fs long, Ti:Sa based laser pulses of 1 PW (VEGA-3), 200 TW (VEGA-2) and 20 TW (VEGA-1) working at a repetition rate up to 10 Hz.


The VEGA2 laser system has been successfully commissioned in 2016-2017 in two different configurations respectively for electron and proton. The first call for user has been run in 2018 with several International recognised research teams. The PW laser (VEGA-3) is now fully operative, and commissioning experiments will start in 2019. A new call for users has been issued offering VEGA-2, VEGA-3, and VEGA-2-based secondary sources (electrons, protons and X-rays).  The first VEGA-3 experiment is planned for September 2019.


The combination of laser intensity, short duration and repetition rate offered by VEGA pave the way for new exiting experiments but also represent a scientific and technological challenge for what concern Targetry and Diagnostic techniques.


Here a first report on the scientific activities of the last years at CLPU is presented focused on:

i)             The first  commissioning campaign

ii)            The  first user access campaign

iii)           The scientific program for targetry and diagnostic development @ HRR

Dátum: 2019. július 19.

Előadás címe: Beam-Fusion-Triggered Transmutator

Előadó: Joshua Edward Tanner


Overview of propsed transmutator driven by fusion neutrons (at 14.1 MeV) in a solution of molten salt (FLiBe/FLiNaK), with a further focus on neutronics simulation. Seminar to cover: A brief review of the state of nuclear waste policy and the need to develop waste management technologies (toilet science). The proposed transmutator, utilizing laser driven ion acceleration triggered fusion neutron sources, and transmutation in minor actide carrying molten salt medium. Basics of nuclear simulation through transport and depletion. Linkage code development and future directions with an emphasis on AI optimization.

Dátum: 2019. június 21.

Előadás címe: Properties and applications of crystalline mirror coatings

Előadó: Ugur Sezer


Substrate-transferred crystalline coatings exhibit tenfold decrease in Brownian noise and 30 times higher thermal conductivity (20-30 Wm-1K-1) compared to IBS coatings. The ultra-low noise character of these semiconductor coatings is especially used for laser stabilization in optical clocks. Additionally, crystalline coatings have superior performance in the mid-IR spectral range exhibiting excess losses down to 50 ppm. Coupled with direct bonding to thermally-optimized substrates, this technology enables significant performance enhancements in high-power solid-state disk and semiconductor laser systems. In collaborative efforts we show that our direct bonding technology can not only enhance the thermal management of high-power laser systems, but also the mechanical rigidity and surface quality of the bonded elements.

Dátum: 2019. május 22.

Előadás címe: How to publish with Springer Nature?

Előadó: Nabil Khelifi (Springer Nature szerkesztő)


-          About Springer Nature

-          Copyright, Authors’ Right, Open Access

-          Journal Publishing

-          Publication Ethics – Research Integrity

-          Book Publishing

Dátum: 2019. május 17.

Előadás címe: Klein-Gordon radio and laser acceleration of particles. Part II.

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


In the first part we have shown that the four potential of electromagnetic fields in a plasma medium can be considered as a massive vector field, where the mass is proportional with the plasma frequency. The plane waves of this »Lánczos-Proca fields« have three orthogonal polarizatons, whose amplitudes satisfy the Klein-Gordon equation. The expression „Klein-Gordon radio” in the title of our talks has been borrowed from the paper by Crandall and Wheeler [1], devoted to the study on a dynamical bound of photon mass. These authors presented the peculiarities of wave propagation in free space, such as the appearance of wake-fields and the special Doppler effect of radio signals from a rapidly receding massy-photon transmitter. We have indicated that similar phenomena are also relevant in the so-called laser wake-field accelerators and in the generation of high harmonics (and attosecond pulses) in a plasma environment. In this second part of the presentation, on the basis of recently found new exact solutions of the relativistic wave equations of charged particles [2], we also show that very high contrast density modulations are generated, serving as »quantum bubbles« to accelerate electrons [3]. We also consider exact analytic solutions of the relativistic equation of motion of a point electron interacting with a high-intensity laser field in vacuum and in a plasma medium [4], and compare the particle dynamics and the radiation properties [5] in these two cases. 
[1] Crandall R E, Wheeler N A, Klein-Gordon radio and the problem of photon mass. Nuovo Cim. 80B, 231 (1984).
[2] Varró S, New exact solutions of the Klein-Gordon and Dirac equations of a charged particle propagating in a strong laser field in an underdense plasma. Nucl. Instr. and Methods in Phys. Research A  740, 280-283 (2014).
[3] Varró S, Quantum description of relativistic charged particles interacting with a strong laser field in a plasma, represented by Lanczos-Proca vector bosons. Talk presented at EUCALL Joint Foresight Topical Workshop: Theory and Simulation of Photon-Matter Interactions [ELI-ALPS, 1-6 July 2018, Szeged, Hungary].
[4]Pocsai M A, Varró S and Barna I F, Electron acceleration in underdense plasmas described with a classical effective theory. Laser and Particle Beams 33, 307-313 (2015). E-print: arXiv: 1406.6310 [nucl-th].
[5] Hack Sz, Varró S and Czirják A, Carrier-envelope phase controlled isolated attosecond pulses in the nm wavelength range, based on coherent nonlinear Thomson backscattering. New J. Phys. 20, 073043 (2018).

Dátum: 2019. május 8.

Előadás címe: From discovery to publishing, how to improve your researcher journey with Web of Science

Előadó: Enikő Tóth-Szász (Clarivate Analytics)


Web of Science Core Collection is the largest editorially curated citation database.  During this presentation we will show, how Web of Science can help you identify discoveries and research useful to advance your own path to innovation and discovery. We will also show how you can optimize the use of Web of Science, Endnote, Kopernio and other tools available to experience a more efficient workflow, from reading to publishing papers.

Dátum: 2019. május 3.

Előadás címe: Klein-Gordon radio and laser acceleration of particles

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


In the present talk,  first we show that the four potential of electromagnetic fields in a plasma medium can be considered as a massive vector boson field, where the mass is proportional with the plasma frequency. Similar vector fields has long been known in quantum electrodynamics from the works of Lánczos [1] and Proca [2], but these do not rely on plasma considerations. The „mass-generation mechanism” has been described by Anderson [3] in solid state physics, and the research in particle physics on this subject has recently culminated in the detection of the Higgs particle [4].

The plane waves of the »Lánczos-Proca fields« have three orthogonal polarizatons, whose amplitudes satisfy the Klein-Gordon equation. The expression „Klein-Gordon radio” in the title of the present talk has been borrowed from the paper by Crandall and Wheeler [5], devoted to the study of a dynamical bound on photon mass. These authors presented the peculiarities of wave propagation in free space, such as the appearance of wake-fields and the special Doppler effect of radio signals from a rapidly receding massy-photon transmitter. We show that similar phenomena are also relevant in the so-called laser wake-field accelerators and in the generation of high harmonics (and attosecond pulses) by relativistic electrons, interacting with extremely high intensity laser fields in a plasma environment. On the basis of recently found new exact solutions of the relativistic wave equations of charged particles [6], we also show that very high contrast density modulations are generated, serving as »quantum bubbles« to accelerate electrons [7]. In the last part of the talk we consider exact analytic solutions of the relativistic equation of motion of a point electron interacting with a high-intensity laser field in vacuum [8] and in a plasma medium, and compare the particle dynamics (laser acceleration) and the radiation properties (attosecond light pulse generation) in these two cases. 



[1] Lánczos C, Die tensoranalytischen Beziehungen der Diracschen Gleichung. Z. für Physik 57, 447 (1929).

[2] Proca A, Sur la théorie ondulatoire des électrons positifs et négatifs. J. Phys. Radium 7, 347-353 (1936).

[3] Anderson P W, Plasmons, gauge invariance, and mass. Phys. Rev. 130, 439-442 (1963).

[4] Higgs P W, Evading the Goldstone theorem. Ann. Phys. (Berlin) 526, 211-213 (2014). [Nobel Lecture, 8 December 2013.]

[5] Crandall R E, Wheeler N A, Klein-Gordon radio and the problem of photon mass. Nuovo Cim. 80B, 231-242 (1984).

[6] Varró S, New exact solutions of the Klein-Gordon and Dirac equations of a charged particle propagating in a strong laser field in an underdense plasma. Nucl. Instr. and Methods in Phys. Research A  740, 280-283 (2014).

[7] Varró S, Quantum description of relativistic charged particles interacting with a strong laser field in a plasma, represented by Lanczos-Proca vector bosons. Talk presented at EUCALL Joint Foresight Topical Workshop: Theory and Simulation of Photon-Matter Interactions [ELI-ALPS, 1-6 July 2018, Szeged, Hungary].

[8] Hack Sz, Varró S and Czirják A, Carrier-envelope phase controlled isolated attosecond pulses in the nm wavelength range, based on coherent nonlinear Thomson backscattering. New J. Phys. 20, 073043 (2018).

Dátum: 2019. április 12.

Előadás címe: Machines tasting wine

Előadó: Zsolt Divéki (ELI-ALPS)


Have you ever wondered who writes the description on the wine label sold in supermarkets? If done by experts, they are called sommeliers. They are professional wine experts with wide range of knowledge about wine service and pairing it with food.

One of the hardest things is to master blind tasting. Blind tasting is when a person is served a glass of wine (or other alcohol) and his task is to describe its characteristics, like color, body, acidity, taste, smell etc. Depending on the difficulty of the tasting the person might be further requested to guess the grape variety, vintage, country of origin etc. of that wine based on the features he just described.

This sounds much like a machine learning task: based on a given description of wine characteristics decide what grape was used to produce the wine, in which country, what vintage etc.

The seminar will present a simple application of how data mining and simple supervised machine learning techniques can be applied to create a simple but still powerful code to guess the grape variety of which a bottle of wine was made from.

Dátum: 2019. március 29.

Előadás címe: The influence of a strong infrared radiation field on the conductance properties of doped semiconductors

Előadó: Imre F. Barna (ELI-ALPS)


This work presents an analytic angular differential cross section formula for the electromagnetic radiation field-assisted electron scattering on impurities in semiconductors. These impurities are approximated with various model potentials. The scattered electrons are described with the well-known Volkov wave function, which has been used to describe strong laser field matter interaction for more than half a century, which exactly describes the interaction of the electron with the external oscillating field. These calculations show that the electron conductance in a semiconductor could be enhanced by an order of magnitude if an infrared electromagnetic field is present with 10^11 W/cm^2 < I <10^13 W/cm2^ intensity.

Reference: Imre Ferenc Barna, Mihály András Pocsai, and Sándor Varró, Eur. Phys. J. Appl. Phys. 84, 20101 (2018)

Dátum: 2019. március 11.

Előadás címe: Introduction of physical experiments at SG-II facility

Előadó: Huiya Liu (Shanghai Institute of Optics and Fine Mechanics )


SG-II facility consists of four sets of lasers, including the nanosecond, picosecond and femtosecond duration pulses. Researchers can conduct varies physical experiments, such as Inertial Confinement Fusion, laboratory astrophysics and particle acceleration. In the first part of the presentation, we mainly describe our experiments conducted on the SGII facility. It includes the study of suprathermal electrons produced by laser-plasma instabilities, the evolution of filaments and associated magnetic fields produced by Weibel instability in two counterstreaming laser plasmas and proton imaging by the picosecond petawatt laser pulse. In the second part, we will describe our target chamber size and the current diagnostics at the facility, which will help external research teams carry out experiments.

Dátum: 2019. március 11.

Előadás címe: Photon-sieve splitter and its application in X-ray holography, phase-contrast imaging and meter-scale wavefront measurement

Előadó: Junyong Zhang (Shanghai Institute of Optics and Fine Mechanics )


Refractive lenses cannot be applied to short-wavelength region by their inherent strong absorption. Relatively, diffractive optical element (DOE) can be used for EUV and soft X-ray focusing and imaging. As a representative of classical DOE, photon sieve derived from the traditional Fresnel zone plate was first proposed in 2001. Furthermore, it can achieve higher resolution on the same component scale. Compared with the monofocal photon sieve, we proposed Greek-ladder sieves to generate three-dimensional array diffraction-limited foci in 2015. Based on Greek-ladder sieve, we here give a brief overview of our recent research on the phase-shifting X-ray digital holography, multiplanar imaging with different point spread functions and phase-contrast imaging, and do some exploration and research on the meter-scale wavefront measurement.

Dátum: 2019. március 11.

Előadás címe: Introduction of Multifunctional Laser Facilities in National Laboratory on High Power Laser and Physics

Előadó: Ping Zhu (Shanghai Institute of Optics and Fine Mechanics )


As the major pioneer devoted to high-power laser technology and inertial confinement fusion (ICF) research in China, the National Laboratory on High Power Laser and Physics (NLHPLP) in Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences has established a multifunctional high power laser experimental platform, which can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. We will introduce this multifunctional experimental platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, and present the key technologies for the eight-beam nanosecond laser system, the picosecond petawatt system, and femtosecond multi-petawatt system, which have been developed to ensure the performance of the facilities. The multifunctional high power laser experimental platform at NLHPLP is operational and available for interested scientists studying ICF and a broad range of high-energy-density physics. Both the physics experiment cooperation and the laser technology collaboration are welcomed at NLHPLP.

Dátum: 2018. december 10.

Előadás címe: Two-electron atoms with correct cusp conditions

Előadó: András Kruppa ((HAS Institute for Nuclear Physics, Debrecen, Hungary))


Finite terms Hylleraas- and Kinoshita-type variational wave functions are considered for three-body systems.

For calculation of the energies the stochastic variational method is applied. This approach leads to significant decrease of the number of terms present in the trial wave function.

In Coulombic case local properties of wave functions are restricted by the Kato's cusp conditions. It is showed that Kato's cusp conditions restrict the possible terms in variational calculations. Constraints for the linear expansion coefficients are also derived and a recursion type solution is given. Local and global properties of wave functions with correct cusp conditions are studied, finally the double-electron photoionization is considered.

In our latest study new sets of functions with arbitrary large finite cardinality are constructed for two-electron atoms. Functions from these sets exactly satisfy the Kato's cusp conditions. The new functions are special linear combinations of Hylleraas- and/or Kinoshita-type terms. Standard variational calculation, leading to matrix eigenvalue problem,  can be carried out to calculate the energies of the system.

There is no need for optimization with constraints to satisfy the cusp conditions.

Dátum: 2018. november 8.

Előadás címe: How modern neutron science helps answering the materials research questions of our time from magnetism to biology

Előadó: Prof. Helmut Schober (Director of the Institute Laue-Langevin, Grenoble)


Today’s materials research is unthinkable without the analytical tools that allow studying structure and dynamics from the subatomic to the macroscopic level.

Among those tools neutron scattering occupies a prominent position given the particular properties of the neutron as a probe.

Recent progress in instrumentation has contributed to reinforcing the role of neutron scattering making it accessible to an even wider range of users.

In this presentation modern neutron scattering as a tool for materials investigations will be briefly introduced. Then, by highlighting recent scientific results, the scientific potential of neutron scattering will be illustrated. The topics will range from fundamental questions in magnetism to structural biology.

In order to make the talk accessible to a broad audience the accent will be placed on the scientific impact of the experiments avoiding technical details.

Dátum: 2018. október 26.

Előadás címe: Ultrafast Coherent Multidimensional Electronic Spectroscopy and its applications to the study of Excitation Energy Transfer Processes in Photosynthetic Light Harvesting Complexes

Előadó: Howe-Siang Tan


Ultrafast Coherent Multidimensional Electronic Spectroscopic belongs to the family of ultrafast nonlinear optical spectroscopy, and is an improvement over conventional ultrafast pump probe (transient absorption) spectroscopy, as it has the ability to resolve both the excitation and detection frequencies in an ultrafast experiment while still maintaining femtosecond time resolution. We will describe our efforts in the development and applications of these techniques to the study of excitation energy transfer (EET) processes in photosynthetic light-harvesting antenna systems.

Dátum: 2018. szeptember 21.

Előadás címe: Recent Research on Laser-Plasma Electron Acceleration & Secondary Sources at Shanghai JT University

Előadó: Nasr Hafz (ELI-ALPS, leader of Electron Acceleration Group)


Laser-plasma particle acceleration is a non-traditional acceleration technique that could lead to a significant downsizing of future high-energy accelerators [1-2].  Recently we conducted laser-plasma electron acceleration research in Shanghai, China. Experiments were based upon a newly-installed 200 TW 30 fs Ti:sapphire laser. We performed a few types of laser wakefield acceleration (LWFA) experiments; the first was based on the self-injection of electrons in 4 mm long He plasma interacted with 30 TW laser pulses (a0 ~1.2). We observed ~120 MeV electron beams with ~ 40 % energy-spread [3]. In order to improve the electron beams we conducted a second type of experiments where we employed the ionization-injection mechanism, by which we observed a significant enhancement of the beam energy up to 400 MeV and a reduction of the energy-spread to 4% [4]. In a follow-up experiment on ionization injection, and in order to boost the electron energy and quality, we employed ~ 120 TW laser pulses and 1 cm-scale plasma. Here we observed narrow energy-spread beams (7 %) with 1.2 giga-electron volts peak energy; see Fig. 1 [5]. The experimental results and the involved physics were all verified by 3D-PIC simulations using OSIRIS code. Additionally, we have measured the emission of synchrotron x-rays (due to the betatron oscillations) from the accelerated relativistic electrons; few mrad, hard x-ray beams with energy up to 100 keV were observed [6]. Finally, by the electrodynamics process of bremsstrahlung we have observed electron-position pairs with energies of 100 MeV and 10 MeV gamma ray beams [7]. In my talk, some of those topics [8] will be discussed in details.

Dátum: 2018. szeptember 4.

Előadás címe: The grateful infrared – novel IR techniques to probe the functional changes of membrane proteins

Előadó: Prof. Dr. Joachim Heberle (Freie Universität Berlin)


The catalytic activity of proteins is a function of structural changes. Very often these are as minute as protonation changes, hydrogen bonding changes and amino acid side chain reorientations. To resolve these, a methodology is afforded that not only provides the molecular sensitivity but allows to trace the sequence of these hierarchical reactions at the same time. I will showcase results from time-resolved IR spectroscopy [1,2] which was applied to channelrhodopsin [3].  Channelrhodopsin represents the first light-activated ion channel to found the basis of the new and exciting field of optogenetics [4]. I shall also provide an outlook towards novel experimental approaches like THz pump / IR probe spectroscopy or near-field IR nanoscopy (see figure below) that are currently developed in my lab [5]. We believe that some of these approaches have the potential to provide new science.

Dátum: 2018. szeptember 3.

Előadás címe: Short FEL pulse in FERMI

Előadó: Najmeh S. Mirian (ELETTRA Sinchrotrone, Trieste, Italy)


FERMI is an externally seeded FEL source, based on the high-gain harmonic generation scheme (HGHG). FERMI has two FEL line, FEL-1, which covers the wavelength range between 100 and 17 nm and FEL-2 in the range between 17 and 4 nm. The shortest pulses delivered by FEL-1 ad FEL-2 have respectively a duration of 40-90 fs and 20-30 fs according to pulse duration scaling with the wavelength.

Controlling pulse duration, and, more generally, the temporal intensity profile of free-electron laser (FEL) pulses, would permit to resolve faster processes, as electronic rearrangements and exploration of electronic motions and nuclear phenomena. This possibility would extend the experiments targeted by FERMI.

In this talk I present the methods that could be used to reduce the pulse length in FERMI and explain how we measure the pulse shape of an extreme ultraviolet externally seeded FEL operating in high-gain harmonic generation mode.

Dátum: 2018. augusztus 31.

Előadás címe: Probing complex light-matter interactions with helium nanoplasmas

Előadó: Marcel Mudrich (Egyetemi docens, Fizikai és Csillagászati Tanszék, Albert-Ludwigs Egyetem, Freiburg)


Nanoplasmas formed from doped helium nanodroplets by irradiation with intense laser pulses feature peculiar properties. In the NIR range, a helium ionization avalanche is triggered by tunnel ionization of the dopant cluster at comparatively low light intensities (~1014 W/cm2). Subsequent light absorption is enhanced by resonances due to nanoplasma anisotropies [PRL 107, 173402 (2011)] and expansion [NJP 14 075016 (2012)]. Consequently, dopant and helium atoms charge up to high charge states [J. Mod. Opt. 64, 1061 (2017)], and energetic ions and electrons are emitted by Coulomb explosion. Surprisingly, recent single-shot velocity-map images of nanoplasma electrons display sharp electron energies peaked at ~1 eV energies. Prospects for probing helium nanoplasmas driven by intense MIR and XUV laser pulses are discussed.

Dátum: 2018. július 25.

Előadás címe: Extreme light from ELI and beyond – Science of high energy, single-cycled lasers

Előadó: Prof. Gérard Mourou


An existing CPA high power laser pulse such as a commercially available PW laser could be readily converted into a single-cycled laser pulse in the 10PW regime without significant loss of energy through the compression. We will describe a way to attain this goal heralding a new set of fascinating applications to science, including medicine, environmental and material science. These include a laser ion accelerator, called single-cycle laser acceleration (SCLA), and bow wake electron acceleration. In addition, in the X-ray regime, single-cycled laser pulses may be readily converted through relativistic compression into a single cycled, X-ray laser pulse. We argue that it could be the quickest and very innovative way to ascend to the EW (Exawatt) and zs (zeptosecond) regime. In this talk we will cover the generation of single-cycled pulse and its numerous and revolutionary applications

Dátum: 2018. július 17.

Előadás címe: Spectra-Physics Lasers: 55 years of laser innovation, manufacturing and application

Előadó: Rob Wolf (A Spectra Physics képviselője)


An overview discussion about Spectra-Physics Lasers, capabilities, products and applications.  Emphasis on laser technologies designed for research laboratories, particularly large laser infrastructure facilities including pump lasers, short pulse ultrafast oscillators and amplifiers and advanced technologies such as CEP and laser synchronization accessories.

Dátum: 2018. május 29.

Előadás címe: Custom Scientific Laser Systems with up to 10 Petawatt Peak Power

Előadó: Gilles Chériaux (National Energetics)


National Energetics is developing high intensity lasers from few tens of Terawatts to 10 Petawatts for scientific applications. These are CPA laser systems based on classic Ti:Sapphire as well as mixed glass, using novel technology for augmented repetition rate at kJ level. Moreover, NE is also providing full remote controls system integrated with the infrastructure.


The presentation will focus on the 10 PW (1500J in 150 fs at 1 shot/minute) laser under construction for ELI-Beamlines. This is a hybrid system with a high contrast OPCPA front-end (4J@5Hz) with spectral shaping capabilities followed by Nd doped-glass amplification for high output energy with split-disk, liquid-cooled technology.

Characteristics of high temporal contrast hybrid system based on short pulse OPCA and classic Ti:Sa amplifiers at 800 nm will also be presented.

Dátum: 2018. május 18.

Előadás címe: Black-body radiation and the discovery of Planck’s constant

Előadó: prof. Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


By deriving the correct formula of the spectral energy density of black-body radiation, Max Planck (1858-1947) discovered in 1900 the fourth fundamental physical constant h, the elementary quantum of action. On the occasion of Planck’s 160th birthday, and the centenary of his receiving the Nobel Prize, we keep track of Planck’s lesser known original thoughts concerning the black-body radiation problem. We point out that, Planck has also solved various other important problems in physics, and his methods and interpretations still may have relevance even today. We shall deal with his so-called second theory, which already contained the concept of induced emission and zero-point energy. We shall also show Planck’s original derivation of the natural system of units (Planck length, mass, time and temperature), which plays a distinguished role in cosmological physics.

Dátum: 2017. szeptember 15.

Előadás címe: Stimulated emission, multiphoton processes and attosecond science viewed from a historical perspective

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


The process of stimulated emission of radiation will be discussed, first in the context of black-body radiation, as it appeared more than hundred years ago in the works of Planck and Einstein. Later results concerning negative absorption, amplification and laser action will also be reviewed, including multiphoton processes which take place during the interaction of very-large-intensity lasers with various constituents of matter. These high-order processes result in large spectral broadening, and may lead to extreme temporal localization of the signals, thus yielding e.g. attosecond light pulses. The development of theoretical methods, interpretations and some examples of basic experimental achievements will be analysed. At the centenary of the first publications on the concept of stimulated emission, we attempt to build a bridge between the early thoughts and recent studies of attosecond and strong-field science.

Dátum: 2017. szeptember 8.

Előadás címe: Electron dynamics in strong laser fields

Előadó: Prof. Hans-Jörg Kull (Institute for Theory of Statistical Physics, Laser Physics Group, RWTH Aachen University)


Strong and short laser pulses provide new experimental techniques to study electronic motion on atomic scales. In above threshold ionization of atoms, the energy gain of photoelectrons is increased by electron-ion collisions. Heating of plasmas by inverse bremsstrahlung absorption is based on electron-ion collisions correlated by the laser field. In this talk we will review and extend theories and computations on electron-ion collisions and above threshold ionization in strong laser fields. Starting from classical instantaneous collisions, we illustrate time-dependent behaviour by a classical binary collision model. The quantum-mechanical behaviour is then studied in terms of numerical solutions of the time-dependent Schrödinger equation[1] and by analyzing the evolution of the corresponding Wigner quasi-probability in phase space[2, 3].

[1] G. Rascol, H. Bachau, V. T. Tikhonchuk, H.-J. Kull, T. Ristow, Phys. Plasmas 13, 103108 (2006).

[2] H.-J. Kull, New J. Phys. 14, 055013 (2012).

[3] C. Baumann, H.-J. Kull, and G.M. Fraiman, Phys. Rev. A 92, 063420 (2015).

Dátum: 2017. május 12.

Előadás címe: Exotic topological phase transitions in TlBiS2 and monolayer AsSb

Előadó: prof. Udo Schwingenschlögl


The potential of TlBiS2 to exhibit topological phase transitions is addressed by computational methods based on parity and surface state analyses. Zero, one, and four Dirac cones are found for the (111) surface under growing hydrostatic pressure. The Dirac cones at thepoints are anisotropic with large out-of-plane spin component. TlBiS2 realizes normal, topological, and topological crystalline insulator phases, thus being the first compound to exhibit a phase transition between topological and topological crystalline insulators. While monolayer As and AsSb are semiconductors (direct band gap at thepoint), fluorination results in Dirac states at thepoints. Fluorinated monolayer As shows a band gap of 0.16 eV due to spin-orbit coupling and fluorinated AsSb a band gap of 0.37 eV due to inversion symmetry breaking. Calculations of the edge states of nanoribbons by the tight-binding method demonstrate that fluorinated monolayer As is topologically nontrivial in contrast to fluorinated monolayer AsSb.

Dátum: 2017. április 21.

Előadás címe: Femtosecond soft X-ray Spectroscopy for Femtochemistry and Photovoltaics

Előadó: Dr. Martina dell’Angela (Istituto Officina dei Materiali, ELETTRA Trieste, Italy)


The study of charge dynamics in chemical processes at surfaces by measuring in real time the changes of the electronic structure of the materials is nowadays possible thanks to the advent of free-electron lasers FELs. We studied photocatalytic reactions at surfaces by recording electronic structure changes in the femtosecond and picosecond timescale after an optical excitation. I will briefly present our time resolved resonant x-ray emission (RXES) study at FELs of the first picoseconds in CO desorption and oxidation reactions triggered by optical pulses [1, 2]. Besides photon in-photon out probing techniques like RXES, photon in-electron out techniques like PES can also be employed for the electronic structure study. I will discuss the advantages and limitations on the usage of time resolved photoemission (PES) for such measurements at FELs [3]. I will present a preliminary time resolved PES experiment performed at a synchrotron facility to explore the charge dynamics induced by sunlight in donor/acceptor molecular systems and describe the set-up for optical pump- PES probe we are are currently building at ALOISA beamline of the Elettra synchrotron.

Dátum: 2017. március 24.

Előadás címe: Measurement of Nanoplasmonic Field Enhancement with Ultrafast Photoemission

Előadó: Judit Budai (Ultrafast Nanoscience Group, Scientific Applications Division)


The measurement of nanoplasmonic near fields is a fundamental question of nanooptics.A new method [1] was introduced at the beginning of this year that utilizes ultrafast photoemission from plasmonic nanostructures and is capable of probing the maximum nanoplasmonic field enhancement.
In this talk I will give a short introduction to plasmonic structures, present the details of the new method and give insight into the finite-difference time-domain simulations that were performed at ELI-ALPS for the validation of the field enhancement values measured by applying the novel approach.

Dátum: 2017. március 9.

Előadás címe: Presentation and interactive discussions on New Laser Glass Materials and Components, Manufacturing and Coating of Ultraprecise Laser Glass Components

Előadó: Todd Jaeger


Laser use is ubiquitous in everyday life. What was once a solution seeking a problem is now present in the production of nearly everything we touch. New applications need new materials to address the broad range of today’s technology. Laser glass, once perceived as useful only in complex scientific applications, is now finding its way into a wide array of commercial, medical and consumer-based uses. Brought about by advances over the last several years in new formulations of laser glass created by SCHOTT, these new gain materials move advanced laser technology from the hands of highly skilled technicians and PhDs and into robust commercial uses. Of particular interest are SCHOTT’s latest formulations: BLG-80 and LG960 Laser Glass.
There are many difficulties involved in the manufacture of ultraprecise glass components and coatings that have the durability to withstand laser radiation with very high power density. These include how best to polish and clean the glass, how to minimize subsurface damage, the ideal approach to coating, the right materials to use, how to increase the Laser Induced Damage Threshold (LIDT), and the many tradeoffs involved.

Dátum: 2017. január 13.

Előadás címe: Multidimensional Electronic Spectroscopy of Energy Transfer in Photosynthetic Systems

Előadó: Petar Lambrev (head of Laboratory of Photosynthetic Membranes, Biological Research Centre, Szeged)


Photosynthesis is initiated by capturing photon energy and creating electronic excitations in the photosynthetic light-harvesting complexes. The overall efficiency of photosynthesis depends on the ability to transfer the excitation energy to the photochemical reaction centre without losses. Resolving energy transfer, which involves many ultrafast steps between molecules with near-identical spectral properties, is a challenging experimental task. Two-dimensional electronic spectroscopy (2DES) is a powerful experimental technique that can map energy transfer pathways by correlating the excited state energies of the donor and acceptor states and following the process in time. Multistep energy transfer can directly be probed by three-dimensional spectroscopy (3DES) that, in turn, correlates the energies of the donor, intermediate and acceptor states and the respective energy transfer time scales. Our 2DES and 3DES experiments on plant light-harvesting complex II reveal the pathways and dynamics of energy transfer in extraordinary detail.

Dátum: 2016. november 25.

Előadás címe: Wide-angle interference of a single-photon emitter for measuring its position on nanometer scale

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


Single-photon wide-angle intereference phenomena have been studied theoretically for glass-diamond-oil and glass-diamond-air layered structures. As a single optical emitter (of wavelength e.g. 637 nm) onenitrogen-vacancy center (NV-center) has been assumed, which is placed close to the upper side of a diamond plate, and it was represented by a Hertzian dipole of arbitrary orientation. The interference fields can be imagined as resultans of superposition of rays emanating from the NV-center directly upwards and from those which are emanating downwards and undergo total internal reflection at the lower surface of the diamond plate of thicknesse.g. 0.1mm = 100000 nm [1]. The direct and the reflected rays recombine on the upper side, and we have proved that also the far-field interference pattern is sensitive to the vertical position of the NV-center (see illustration in Figure 1). As is seen, e.g. 2nm difference in distance of the emitter from the upper surface of the diamont results in an angular shift of order 0.01 degree of the pattern, which should already be a measurable effect.

Dátum: 2016. október 11.

Előadás címe: Hypervalent Carbon, or How to Freeze the SN2 Transition State

Előadó: Prof. Matthias Bickelhaupt (Amsterdam Center for Multiscale Modeling, Vrije Universiteit Amsterdam, and Radboud University, Nijmegen, The Netherlands)


Silicon in [Cl-SiH3-Cl]– is hypervalent whereas carbon in [Cl-CH3-Cl]– is not. The latter species is a first-order saddle point, a transition state for bimolecular nucleophilic substitution (SN2) reaction, which connects two stable, tetra-valent carbon species. In this talk, I show how the different behavior of silicon and carbon can be understood in terms of the Ball-in-a-Box (BiaB) model, based on modern Kohn-Sham molecular orbital (KS-MO) theory. The illustration below is an artist's impression of the essence of the BiaB. It holds the clue to answering the question about the different bonding capabilities of C and Si.

Proceeding from the insights emerging from KS-MO analyses and the above BiaB, I will develop a strategy for creating a stable species involving a truly hypervalent, five-coordinate carbon atom. If successful, this quest would come down to a violation of the octet rule for carbon! One might conceive this also as "freezing" the SN2 transition state, turning the otherwise labile species into a stable equilibrium structure.

Dátum: 2016. szeptember 26.

Előadás címe: The Intellectual Property Policy of ELI-HU Ltd, and the management of IPs at ELI-HU Ltd.

Előadó: István Molnár


Topics to be addressed:
a) Introduction of the IP Policy at ELI;
b) The objectives of the IP Policy;
c) The subject matter IP according to the IP Policy;
d) The employees and agents subject to the IP Policy;
e) Remuneration of the inventors according to the IP Policy;
f) Procedures and responsibilities: invention disclosure, IP prosecution, technology-transfer;
g)Valuation of IP;
h) Publications

Dátum: 2016. szeptember 9.

Előadás címe: Modeling and experimental benchmarking of a high repetition rate laser-plasma hard x-ray source

Előadó: Dániel Papp


Laser-plasma based high repetition-rate hard (6 keV+) x-ray sources were the subject of extensive studies, with such systems implemented at research facilities and available commercially. Such x-ray sources are used in diverse pump-probe experiments and also have prospective biomedical imaging applications. The operational regime of such sources can be extended into the ultrafast (10-50 fs) range with a tabletop setup, with few-cycle driving lasers and suitable target selection.
In this talk I will discuss the physical processes in the generation of hard x-rays in such sources. These processes were modeled using the EPOCH Particle-In-Cell and GEANT4 Monte-Carlo code packages. Experiments were conducted on an ultrashort pulse, 1 kHz repetition-rate laser using solid targets at the CLPU laser facility in Salamanca, Spain. The obtained experimental results were used for benchmarking the simulation.

Dátum: 2016. szeptember 2.

Előadás címe: Scattering of ultrashort electromagnetic pulses on a system of two parallel current sheets: the role of the radiation reaction and of the time delay

Előadó: Mónika Polner


The reflection and transmission of a few-cycle laser pulse impinging on two parallel thin metal layers have been analyzed. Our model is an extension of the one-layer scattering problem described in [1-3], and the analysis is based on classical electrodynamics and mechanics. The two layers, with thickness much smaller than the skin depth of the radiation field, are represented by current sheets, which are embedded in three dielectrics, all with different index of refraction. The dynamics of the surface currents and the complete radiation field are described by the coupled system of Maxwell-Lorentz equations.

In our analysis particular attention has been paid to the role of the radiation reaction and of the time delay. There are several sources of time delay in the extended system: due to the angle of incidence of the impinging laser pulse and due to the propagation time between the two surface current sheets. In this presentation we show the analytic solution of the resulting coupled delay differential-difference system of equations when the three dielectrics have the same index of refraction, besides, we show some numerical studies of the most general case. The main emphasis is on the effect of the delay on the dynamics of the system.

Dátum: 2016. július 8.

Előadás címe: Beam transport and monitoring of laser-driven particle beams

Előadó: Jörg Pawelke (OncoRay – National Center for Radiation Research in Oncology, Dresden, Germany; Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden; and Helmholtz-Zentrum Dresden-Rossendorf)


Particle acceleration by high intensity lasers promises more compact and cost effective ion sources as well as electron beams of very high energy for radiotherapy application. In contrast to pencil-like, monoenergetic, and (quasi) continuous beams from conventional accelerators, laser-driven beams are characterized by short pulses of very high particle flux, low repetition rate, broad energy spectrum, large divergence and significant pulse-to-pulse fluctuation. In consequence, a future medical application requires not only a high power laser system and laser target to generate particle beams of therapeutic quality but also new technical solutions for suitable beam detection and dosimetry, beam transport, dose delivery including treatment planning along with research on the radiobiological consequences of short radiation pulses with ultra-high pulse dose rate. The status of the ongoing joint translational research project onCOOPtics of several institutions in Germany will be presented with an emphasis on beam detection and beam transport via pulsed magnets.

Dátum: 2016. július 1.

Előadás címe: Short Wavelength Radiation in Laser-Plasma Interactions

Előadó: Zsolt Lécz


Interaction of relativistically intense laser pulses with matter involves highly nonlinear processes and produces energetic charged particles and photons with unique properties. Numerous mechanisms have been identified for ion acceleration or for high harmonic acceleration, but their efficiency is usually very low. Our primary goal is to increase the energy conversion efficiency from laser pulse into higher harmonics. The synchrotron radiation emitted by relativistic electrons oscillating in magnetic undulators is a powerful source of short wavelength X-ray radiation. Electrons oscillate at the laser-plasma interface as well, where they have complicated trajectory and can emit synchrotron-like coherent or incoherent radiation, depending on the plasma density and surface structure. In this work we investigate such interactions with solid density cylindrical targets or flat foils equipped with nanorods or microdots on their surfaces. In the presentation we show results of 2D/3D particle in cell simulations, which are helpful tools in modeling of such non-linear phenomena.

Dátum: 2016. június 10.

Előadás címe: Towards ultrafast, nanoscale optical switching

Előadó: Péter Dombi


Nano-optical near fields, generated, for example, by plasmon oscillations have several unique properties. Hundred-times electric field enhancement and few-nanometer field localization of a laser pulse can be easily achieved. If we induce plasmon oscillations with ultrashort pulses, high spatiotemporal localization and highly nonlinear interactions are possible. Both are prerequisites for ultrafast, nano-integrated optical devices. As first steps in this direction, I will show new methods to characterize nano-optical near fields with nanometer resolution and ways to generate nonlinear interactions with low-energy laser pulses.

Dátum: 2016. május 27.

Előadás címe: Chemical and Materials Aspects of Ultrafast Dynamics in Semiconductors: State-of-the-Art and Future Opportunities

Előadó: Csaba Janáky


Various photoinduced processes in semiconductors occur at distinctly different timescales. Ultrafast laser spectroscopy has been long the tool for examining mechanistic aspects of light induced processes in semiconductors as well as at semiconductor interfaces. So far, most of the work has focused mainly on transient absorption spectroscopy, at relatively long timescales (typically ns-ms, sometimes ps), where charge transfer, recombination, and different surface reactions occur. On the other hand, much less is known about the photo-excitation process itself, carrier cooling and trapping, which occurs at the femtosecond timescale.
We aim to understand the peculiar conduction mechanisms (including photoinduced charge carrier formation, exciton dissociation, recombination, etc.) in different classes of semiconductors; such as organic semiconductors (conjugated polymers), different 1D and 2D inorganic semiconductors (this latter group is also called topological insulators, such as MoS2 and NbSe2), and organic-inorganic hybrid materials (for example organic lead halide perovskites). While these materials play an impressively increasing role in different practical applications, very little is known about the fundamentals of the mechanism of (photo)conductivity (which forms the basis of most applications) observed in these materials.
In this talk I will first present the background of the research and some of the previous achievements of the PI. Subsequently, I will summarize the state-of-the-art how ultrafast laser pulses can be employed as tools to characterize the above listed phenomena in different nanomaterials. Among others, I will focus on the physico-chemical implications of temporally (and spatially) resolved two-photon ultraviolet photoelectron spectroscopy, and the nanoscale aspects of time-resolved HZ spectroscopy, from the Chemists’ perspective.Finally, I will highlight some of our future plans.

Dátum: 2016. május 13.

Előadás címe: Probing the structure and dynamics of nanomaterials and molecules

Előadó: Mousumi Upadhyay-Kahaly


Modern technology entails the manipulation of matter on ultrashort scales, and measurement of the dynamic processes in ultrafast domain. Thus "ultrafast science" impacts multiple areas of modern physics, chemistry, biology, materials science, engineering etc. Formation and breaking of chemical bonds occur in femtosecond time scale, and thus, elementary molecular processes can be observed and utilised by freezing the transition states of chemical processes at ultrashort time scale, even shorter than the vibrational and rotational periods in matter. Along with the technological advances, ultrafast lasers, such as in ELI-ALPS, are employed to probe the molecular systems, to understand their time evolution and, to investigate intricate details of the time-resolved behavior of matter.
However limitations in controlling the experimental parameters and data processing requires theoretical tools to support and complement while probing the evolution of the electronic structures post controlled excitation in the time domain. In the presentation, we will discuss structure-function relationships in materials using first principles quantum mechanical calculations based on density functional theory and time dependent density functional theory, touching upon different aspects of novel material synthesis, energetics, lower dimensional systems, organometallic substances etc. We will show how theoretical modeling can be efficiently used to explain/predict the functionalities and material response of nanostructures, solids and molecules, with specific focus on their physical properties under interaction with electromagnetic fields and the dynamics associated with the electronic motions of the structure.

Dátum: 2016. április 15.

Előadás címe: Polarization Encoded Chirped Pulse Amplification in Ti:Sapphire – a Way towards Few Cycle PW Lasers

Előadó: Huabao Cao


We proposed and demonstrated the broadband amplification of short pulses in a polarization encoded (PE) Ti:Sa amplifier. Unlike previous methods based on making a deep in the spectral amplitude of the seed pulse, here the achievable bandwidth is considerably broader along with a lossless overall amplification process. It was shown in our experiments that the PE amplification preserved a bandwidth close to 90 nm of a top hat spectral profile while increasing of the spectral width of a Gaussian pulse by 40%. It was also shown that an additional polarization rotation takes place during the pulse amplification and we suggested to mitigate it with thicker decoding quartz so as to ensure good efficiency, which has been experimentally proved. Because the PE amplifier usually introduces dip in the spectrum, an additional conventional Ti:Sa amplifier was built to smooth the spectrum and also promote the energy. The compressibility of the amplified pulse after the PE amplifier has also been verified by experiment.
According to the simulations, the high energy polarization encoded Ti:Sa amplifiers predicts an amplification bandwidth of 200 nm, making it a promising technique for intermediate and final amplifiers of high field Ti:Sa CPA-laser systems. This technique may pave the way to PW class Ti:Sa lasers with tens of Joule few cycle laser pulses.

Dátum: 2016. április 1.

Előadás címe: High Repetition Rate for Ultra-High Peak Power Laser Systems

Előadó: Vladimi Chvykov


Combination of the large aperture Ti:Sa crystals with EDP-technology of the energy extraction in final amplifiers of ultra-high peak power CPA laser systems allowed to achieve recently the record output of 5 PW. 10 PW laser systems under construction right now in the frame of the ELI project and its final goal 200 PW is on the roadmap. Nevertheless, the increasing repetition rate of the laser systems to 10 Hz even with 1-2 PW of the output power (ELI-ALPS) still is a big challenge for laser technology. In our research we have suggested to add to EDP Ti:Sa combination the third element, namely Thin Disk crystal geometry (EDP-TD) to overcome the limitations associated with thermal cooling of crystal and transverse amplified spontaneous emission in high average power laser systems based on Ti:Sa amplifiers. In this talk we will discuss the possible benefits of this idea, as well as the results ofproof-of-principal experiments where first time, according to our knowledge, the scheme of EDP-TD was tested.

Dátum: 2016. március 18.

Előadás címe: Optimization and simulation for the development of advantageous plasmonic structures

Előadó: Tibor Csendes, Balázs Bánhelyi, and Mária Csete (University of Szeged)


New techniques will be introduced to design tiny optical sensors applying the Matlab based COMSOL simulation program and cleverly formulated constrained nonlinear optimization problems. In this way we could find good solutions that are favorable also with respect topractical realization.We illustrate our methodology on some reallife examples. Details of the technique will be highlighted also regarding the limitations, the huge computational complexity, and the evaluation of the results obtained.

Dátum: 2016. március 9.

Előadás címe: Ionisation induced electron trapping in the linear regime of a laser wakefield accelerator

Előadó: Christos Kamperidis


The scheme of Laser Wakefield electron acceleration (LWFA) has rapidly matured over the past decade, from proof-of-principle experiments to real life applications, such as non-destructive X-ray imaging. The scheme involves the use of >1 TW laser systems and > 1mm long gaseous targets. In this seminar, we will describe the basic principles of LWFA, show how ionisation injection relaxes the laser requirements to achieve stable relativistic electron beams and outline the potential of these ultra-compact relativistic accelerators.

Dátum: 2016. február 26.

Előadás címe: Gravitational waves: prediction, discovery, prospects

Előadó: László Árpád Gergely


101 years ago the concept of Newtonian gravitational force was replaced by space-time curvature. Matter tells space-time how to curve and space-time tells matter how to move. These effects however are not instantaneous. Gravity propagates with the speed of light. The propagating curvature modulations on the background curvature are the gravitational waves. They are easily produced in the regions of the universe, where the energetics is violent, for example, when black holes collide. Such gravitational waves produced 1.3 billion years ago were detected for the first time on September 14th, 2015 by both Advanced LIGO detectors. During their travel through the Universe, the waves weakened such that they produced a deformation of one part of a thousand of the size of the proton, hence the detection by laser interferometry has been an engineering success. The Advanced LIGO detectors will undergo further improvements, and other similar detectors are on the verge of completion. New types of gravitational wave detectors, either space-born or based on radio interferometry are also envisaged. The era of gravitational wave astronomy has begun, a new window to the Universe has opened.

Dátum: 2016. február 19.

Előadás címe: Reaction microscope and data analysis with GO4

Előadó: Miklós Füle


Understanding of the three dimension structure, photochemical dynamics and fragmentation of molecules has improved substantially by variety of spectroscopic method. One of those techniques is the photoelectron spectroscopy in which the high energy photon absorbed by the molecule and an electron ejected subsequently from the atomic system. Based on the new technology development in the last two decades concerning the ultrafast laser technology and time-resolved spectroscopic technology and also the single-particle imagingtechnology a new powerful spectroscopic imaging method has emerged. Measuring the momentum and angular distribution of photofragment the reaction microscope has become the “bubble chambers of atomic and molecular physics”. In this presentation I am going to give a brief introduction to this technique what will be the one of the end stations of ELI-ALPS HR GHHG systems too.

Dátum: 2016. február 19.

Előadás címe: An overview of attosecond pulse generation

Előadó: Fatemeh Aeenehvand


The first part of this talk is focused on theoretical analysis of high-harmonic generation in solids and comparison with gas. The effects of strength field intensity is considered, the results show a simple approximate cutoff law for HHG in solids. The HHG process using the saddle point approximation is also investigated. The second part describes the generation and application of attosecond pulse and VIS/NIR probe pulses. Concerning the characterization of the probe pulses, the temporal duration and the carrier-envelope phase (CEP) stability is investigated, finally, the measurement of charge migration in the amino acid Phenylalanine is demonstrated, and it shows that attosecond science offers the possibility to elucidated process ultimately leading to charge localization in complex molecule.

Dátum: 2016. február 19.

Előadás címe: Introduction to the low density matter end station at FERMI

Előadó: Tamás Csizmadia


The FERMI free-electron laser connected to the Elettra synchrotron storage ring at Trieste (Italy) is one of ELIs strategic partners, which provides ultrashort (10-100 femtosecond) pulses with high brightness in the ultraviolet and soft x-ray wavelength ranges. The tuneable, fully coherent pulses of FERMI open up opportunities for exploring transient electron dynamics and controlling electronic wave packets during a photoionization process in gases. During the seminar, I would like to introduce the Low Density Matter end station at FERMI, the operation of its angularly resolved photoelectron spectrometer during experimental runs, and the methods for data collection, processing and interpretation.

Dátum: 2016. február 12.

Előadás címe: Classical Trajectory Monte Carlo method– „Watching quantum physics in real time”

Előadó: Károly Tőkési


Attosecond physics is a new and rapidly developing field driven by recent advances in laser technology. Attosecond science holds the promise to observe and to control the motion of electrons on their natural time scale. It is now possible to take snapshots of electrons in motion in atoms, molecules, and solids. The long-lasting dream of chemists and physicists to watch and to control in real time the formation and breaking of chemical bonds or electrons leaving an atom is now closer to realization than ever. These experimental advances pose considerable challenges for theory.

Time-resolved photoemission experiments employing attosecond streaking of electrons emitted by an extended ultraviolet pump pulse and probed by a few-cycle near-infrared pulse found a time delay of about 100 as between photoelectrons from the conduction band and those from the 4f core level of tungsten. We present a microscopic simulation of the emission time and energy spectra employing a classical transport theory. Our calculations reproduced well both the emission spectra and streaking images. We found delay times near the lower bound of the experimental data.

Photoemission spectra feature also complex correlation satellite structures signifying the simultaneous excitation of single or multiple plasmons. The time delay of the plasmon satellites relative to the main line can be resolved in attosecond streaking experiments. Time-resolved photoemission thus provides the key to discriminate between intrinsic and extrinsic plasmon excitation. We demonstrate the determination of the branching ratio between intrinsic and extrinsic plasmon generation for simple metals.

Dátum: 2016. február 10.

Előadás címe: XUV induced ultrafast mechanisms in molecular structures: from attosecond physics … to astrochemistry

Előadó: dr. Franck Lépine


Short XUV pulses combine 2 advantages for physicists and chemists, which are motivating the development of intense research programs worldwide. First, high-energy photons allow the generation of highly excited species and second, short duration gives access to ultrafast phenomena in realtime.
In molecules, short XUV pulses can trigger complex dynamics that can be followed in real-time using pump-probe schemes, down to the attosecond time-scale. Due to high photon energy excitation, induced processes imply interaction between all the particles constituting the molecule (so-called: electron correlation, non-adiabatic couplings etc…). Therefore a theoretical description requires state-of-the-art many-body quantum theories.
Being able to perform such “realtime” experiments, combined with accurate theoretical quantum description in increasingly complex systems is a major challenge for the development of the emerging field of attosecond molecular physics. Although challenging, it is expected that this research activity would have major impact in other fields and would nourish analytical chemistry, molecular electronics, astrophysics and fundamental aspects of quantum mechanics in general.
In this talk, I will present the research program developed in my group to extend XUV induced molecular science to the investigation of increasingly large molecular systems.

Dátum: 2016. február 4.

Előadás címe: Soft photon resummation in QED and the Bloch-Nordsieck model

Előadó: Péter Mati


Infrared (IR) singularities in massless gauge theories are known since the foundation of quantum field theories. The root of this problem can be tracked back to the very definition of these long-range interacting theories such as QED. We will briefly review the basics of QED: Lagrangian formalism, Feynman rules, etc... The IR catastrophe and its resolution by cancelling these divergences will be also discussed. The Bloch-Nordsieck model provides the IR limit of QED and in its framework all the radiative corrections to the electron propagator can be fully summed. However, perturbation theory does not provide the right tool for this operation: the exact Dyson-Schwinger (DS) equation needed to be solved with the aid of the Ward-Takahashi identities. Solving the DS equation at finite temperatures is also possible and will be presented in the talk.

Dátum: 2016. január 29.

Előadás címe: Report on development of an all reflective polarization rotator and an Yb:CaF2 thin disk amplifier

Előadó: János Bohus


We present a conceptual design of an RDPR (Reflective device for polarization rotation) as a preferable alternative to conventionally used HWPs (halfwave plates). An RDPR has the advantage over HWPs of better accuracy of the polarization angle of the beamline. Furthermore, the spectral transfer function is widely selectable, due to the purely reflective design. Moreover, the device is scalable in size and the damage threshold is only limited by the mirrors, which is considerably higher than for HWPs. Additionally, in comparison to those, RDPRs create no prepulses leading to postpulses generated in the subsequent high-power short-pulse laser chain. Hence, RDPRs are also suitable for the manipulation of the polarization of compressed, and therefore ultra-short laser pulses.
Furthermore we report on development of a thin disk energetic amplifier based on Yb:CaF2. Results of gain, thermal lensing, depolarisation loss, temperature distribution measurements carried out at Institute of Optic in Paris are presented.

Dátum: 2016. január 29.

Előadás címe: Circularly polarized XUV attosecond pulse trains generated in aligned CO2 molecules

Előadó: Mathieu Dumergue


High order Harmonic Generation (HHG) in gases is the subject of numerous studies since its discovery in 1987-1988. The mechanism of HHG is quite well known in the case of an atomic target, leading to the generation of a linearly polarized XUV attosecond pulse train (or single attosecond pulses under some conditions) with linearly polarized generation field. Unfortunately, the same mechanism forbids the generation of circularly polarized attosecond pulses with atoms and a circularly polarized generation field. In order to overcome this difficulty, several different techniques have been used (two colour HHG, two pulses with opposite helicity, molecular target …).
During this talk, I’ll present an experiment conducted at the FORTH institute in Heraklion, Greece, about the generation of such circularly polarized XUV pulses by HHG in aligned CO2 molecules with circularly polarized generation pulses. Former studies have shown that lower harmonics (the 3rd) can exhibit highly elliptical polarization in the same conditions. The goal of the experiment was to show that higher order harmonics have the same behaviour. I’ll start with a short explanation of the phenomenon and the conditions leading to the generation of circularly polarized XUV pulses, followed by the description of the experimental setup, and finishing with some preliminary results and possible ideas for the improvement of the experiment.

Dátum: 2016. január 29.

Előadás címe: Hard x-ray generation experiments on the 1 kHz 22 fs CEP laser at CLPU

Előadó: Dániel Papp


The talk would describe initial experiments on the 1 kHz CEP laser at CLPU, Salamanca. The laser setup operated at an intensity of 1×1016 Wcm-2. During the campaign, a liquid target setup suitable for 100kHz repetition-rate applications were investigated. A solid copper target on a high-speed target stage was also installed to test x-ray diagnostics, and the installed delay scheme to provide a controlled laser pre-pulse. The controlled laser prepulse allowed a 4-fold increase in Cu K-α hard x-ray yield. The laser-to-x-ray yield was found to be anomalously low compared to expectation based on similar experiments and simulations.

Dátum: 2016. január 22.

Előadás címe: Perspectives for photofission research at the ELI - Nuclear Physics facility

Előadó: Attila Krasznahorkay (H.A.S.-ATOMKI)


The perspectives for photofission experiments at the new Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility will be discussed from a point of view of the necessary detector developments.
Photofission measurements enable selective investigation of extremely deformed nuclear states in the light actinides and can be utilized to better understand the landscape of the multiple-humped potential energy surface (PES) in these nuclei. High resolution studies will be performed on the mass, atomic number, and kinetic energy distributions of the fission fragments following the decay of states in the first, second and third minima of the PES in the region of the light actinides. We aim at investigating the heavy clusterization and the predicted cold valleys of the fission potential. Moreover, a special focus on the fission dynamics and clusterization effects in super- (SD) and hyperdeformed (HD) compound states will be addressed. Such fission barrier parameters are crucial inputs also for cross section calculations in the Thorium-Uranium fuel cycle of 4th generation nuclear power plants.
These studies call for developments of state-of-the-art fission detectors to exploit the unprecedented properties of the high-flux, Compton backscattered γ-beams having a very small beam spot size. A multi-target detector array will be discussed, which is under development at MTA Atomki, consisting of position sensitive gas detector modules based on the state-of-the-art THGEM technology. For the measurement of the mass and atomic number distribution of the fission fragments a highly-efficient, five-folded, Frisch-gridded twin-ionization chamber (used as Bragg ionization chamber), which is also under development at Atomki, will be discussed.The chamber will be equipped with double-sided Si strip detectors in order to measure light particle emission probability from the highly-deformed compound state and to detect ternary particles from fission. Atomic numbers will be extracted by tracking the range of the fragments using fast digitizers and advanced digital signal processing (DSP) techniques.

Dátum: 2016. január 8.

Előadás címe: Exploration of molecular biological effect of laser driven ionizing radiations

Előadó: Bettina Ughy


Understanding of the biological effect of laser driven ionizing radiation is essential for safe and effective therapies. Comparison of the molecular biological effect of laser accelerated ionizing beams to that resulted in using conventional photon and electron is highly important. Investigations in the radiation sciences mainly concentrated on the identification and quantification of types of DNA damage induced by radiation. Nowadays there are increasing interest for development of personalized therapies that are based on the combination of molecular targeted therapy and radiotherapy, which needs deeper understanding of the molecular effect of ionization radiations. Reactive oxygen species (ROS) act as a second messenger in cell signalling and are essential for various biological processes in normal cells. In the case of redox imbalance ROS could be involved in cancer development. On the other hand ionizing radiation induces the formation of free radicals and ROS that could trigger cell death and this way could be used for killing cancerous cells. Because of the double-edged sword property of ROS understanding of ROS production and the related molecular mechanisms is extremely important.

Dátum: 2015. október 30.

Előadás címe: Attosecond Light Sources using Plasma Optics

Előadó: Subhendu Kahaly


State of the art high-power femtosecond lasers have allowed us to achieve light induced coherent control of relativistic matter1, thus opening novel vistas for basic sciences, as well as for scientific and societal applications. The usual trend in this research field has been to attain the highest possible laser intensities on target, by focusing Fourier-Transform Limited ultrashort laser pulses up to their diffraction limit. Such focussed ultrashort intense light can transform any solid surface into an instantly ionised plasma reflector. This type of exotic plasma optics can operate at ultra-high intensities making them extremely attractive and also the only optics available at such high light fields.
We demonstrate that they can act as tuneable reflective2 or diffractive3 elements which can be controlled for surface sharpness2, shape1,4, structure3,5,6 and can be driven over ultrafast timescales to relativistic motion in phase with the driving laser field1,2. The last property lets it also act as a coherent XUV light emitter7 having tremendous potential as an isolated attosecond light source8 for further scientific applications9.
In this presentation I would introduce different exciting schemes to accomplish plasma optics at high intensity and control their various properties that we developed over time1,2,3. In continuation, I would be providing several examples to show that shaping the laser field in space can lead to novel and far-reaching physical effects. Finally I would summarise few of our recent examples to show how these properties permit one innovative applications which are not possible otherwise10.
1. H. Vincenti “Optical properties of relativistic plasma mirrors”, Nature Communications 5, 3403 (2014)
2. S. Kahaly et al. “Direct observation of density-gradient effects in harmonic generation from plasma mirrors”, Phys. Rev. Lett. 110, 175001 (2013)
3. S. Monchoce et al. “Optically controlled solid-density transient plasma gratings”, Phys. Rev. Lett. 112, 145008 (2014)
4. Nakatsutsumi, M. et al. “Fast focusing of short-pulse lasers by innovative plasma optics toward extreme intensity”, Opt. Lett. 35, 2314 (2010).
5. S. Kahaly et al. “Near-complete absorption of intense, ultrashort laser light by sub-λ gratings”, Phys. Rev. Lett. 101, 145001 (2008)
6. M. A. Purvis et al. “Relativistic plasma nanophotonics for ultrahigh energy density physics”, Nature Photonics 7, 796 (2013)
7. C. Thaury and F. Quere “High-order harmonic and attosecond pulse generation on plasma mirrors: basic mechanisms”, J. Phys. B. 43, 213001 (2010)
8. Jonathan A. “Attosecond lighthouses from plasma mirrors”, Nature Photonics6, 829–833 (2012)
9. Maurizio Reduzzi “Advances in high-order harmonic generation sources for time-resolved investigations”, Journal of Electron Spectroscopy and Related Phenomena, Review article in press, (2015)
10. A. Leblanc “Ptychographic measurements of ultrahigh-intensity laser-plasma interactions” Nature Physics, article in press (2015).

Dátum: 2015. október 9.

Előadás címe: Potential application of laser driven ionizing radiation in radiation oncology- radiobiology experiments

Előadó: Katalin Hideghéty


There are growing evidence word wide with hadron therapy of more then 100.000 patients on the superiority of charged particle treatment over conventional photon irradiation, due to its physical characteristics represented by the Bragg peak of the depth dose curve. The consequent high physical selectivity of the dose delivery allows dose escalation in the tumours without increasing the risk of late complication in the surrounding tissues. Furthermore the biological effectivity of certain charged particles could be 4 times higher then the photon beam. Therefore the patients suffering from well circumscribed locally growing tumors with radiosensitive tissues around could have a benefit from charged particle therapy (CPT). The clinical experiences with CPT of eye-, skull base-, CNS-, childhood tumors, prostate carcinoma, breast-, lung-, head and neck malignancies will be briefly summarized. The planned laser-driven ionizing beams at ELI-ALPS have the unique property of ultra-short ion pulses, and high repetion rate which may introduce a new approach in the radiation therapy. Toward the development of laser accelerated particle therapy for the clinic, intensive experimental research on the biological effect of laser driven CPT is essential. An onverview will be provided on the published results of preclinical radiobiology investigations on laser accelerated paricles and on the planned biological experiments at ELI-ALPS. The actual research of our group on special dosimetry and development of appropriate models (tissue cultures of various tumor cells, wild type and transgenis zebrafish embryos, small animals) and methods (detection of survival, functional-, analytic-, cellular-, subcellular- and molecular changes) for comparison of the effect of laser accelerated ionizing beams to that resulted in using conventional photon and electron beams will be presented.

Dátum: 2015. október 2.

Előadás címe: Fact-based Research Management at ELI-ALPS: an Elsevier Workshop

Előadó: Péter Porosz - Elsevier


Today's R&D landscape requires research managers to devise better ways to measure the quality and impact of their institution's research projects. Working with leading research institutions worldwide, Elsevier aims to provide solutions and support the development of research projects at ELI-ALPS.
Elsevier provides research intelligence thorugh Scopus and SciVal, both of which are quickly becoming the accepted global standards by which research programs are planned and evaluated and the result are showcased.
Scopus is the largest abstract and citation database of peer-reviewed literature: scientific journals, books and conference proceedings. Delivering a comprehensive overview of the world's research output in the fields of science, technology, medicine, social sciences, and arts and humanities, Scopus features smart tools to track, analyze and visualize research.
SciVal offers quick, easy access to the research performance of 5,500 research institutions and 220 nations worldwide. A ready-to-use solution with unparalleled power and flexibility, SciVal enables you to visualise research performance, benchmark relative to peers, develop collaborative partnerships and analyze research trends.
In this workshop, we will explore how Elsevier research intelligence can support ELI-ALPS, so that the program can reach its maximal research potential.

Dátum: 2015. szeptember 18.

Előadás címe: The Low Density Matter beamline at the Italian Free Electron Laser FERMI

Előadó: Carlo Callegari (Italian Free Electron Laser FERMI, Trieste)


In this talk the current status and recent results of the Low Density Matter (LDM) beamline at the FERMI Free Electron Laser in Trieste, Italy will be presented.

Free Electron Lasers fulfill the need for soft and hard X-ray radiation with extremely high brilliance, a high degree of (transverse and longitudinal) coherence, and duration in the femtosecond time domain. FERMI covers the spectral range from 100 down to 4 nm and has been designed as a Users’ facility providing stable operation, high spectral purity, full tunability, variable polarization, and low timing jitter. Since the beginning of Users’ operation in December 2012, FERMI has received ~200 proposals, and allocated ~1/3 of them. Three beamlines are open to users (Diffraction and Projection Imaging; Elastic and Inelastic Scattering-TIMEX; Low Density Matter) and three more are scheduled to open in 2016.

The LDM beamline caters to the atomic-, molecular-, and cluster-physics community, offering an endstation for photoelectron, photoion, and photon-scattering spectroscopy of supersonic jets (notably, of helium droplets, which can be used to transport and cool large molecules). Beyond its standard spectrometers (Velocity Map Imaging; ion Time of Flight; photon scattering) the end-station has accommodated user-supplied instruments, for Users’ experiments as well as FERMI characterization experiments.

Dátum: 2015. szeptember 9.

Előadás címe: Nonlinear Microscopy and Applications for Biological Imaging

Előadó: Virginijus Barzda (Chemical and Physical Sciences, University of Toronto)


Advanced optical microscopy is experiencing a renaissance by breaking the diffraction limit of spatial resolution, providing imaging at video frame rates and achieving deep tissue imaging. Significant advancements in microscopy are realized by employing nonlinear light-matter interactions. Many biological structures, when exposed to high intensity femtosecond laser radiation, exhibit harmonic generation effects, and hence, do not require labeling with dyes that can potentially disrupt the functionality of the system. The harmonic imaging is free of photobleaching and carries structural information beyond diffraction limited resolution. Laser scanning harmonic generation microscopy is a versatile imaging technique which can be used to visualize nanostructures, interfaces between materials and ordered biological aggregates. The use of nonlinear microscopy for structural investigations of protein assemblies in cells and biological tissue will be overviewed, and examples of imaging applications in plant biology, tissue pathology in cancer diagnostics, and study of muscle contraction dynamics will be presented.

Dátum: 2015. július 17.

Előadás címe: Beyond the DNA damages: DNA error types, repairs and diseases

Előadó: Tibor Pankotai (Genome Integrity and DNA Repair Group, University of Szeged)


At recent days the understanding of cancer development and progression is one of the highest challenge for the medical sciences. The cases of cancerous malformations show increasing tendency and they affect a huge number of populations. For example, over 30 million new patients were documented in 2013, which means one person is affected out of 200 people all around the world. During cancer development one of the earliest steps is the failure of the DNA repair pathways. If the DNA repair does not function properly or the rate of DNA damage exceeds the repair capacity of the cell, the accumulation of errors can overwhelm the cells, which is resulted in early senescence, apoptosis, or cancer. Until now, mutations of 40 different proteins, involved in different DNA repair pathways, have been reported to increase the rate of cancer formation.
In my talk, I will focus on the introduction of DNA damaging agents and sources, types of DNA damages and cancer hallmarks affected by proteins involved in DNA repair pathways. Additionally, I will give an overview how we could study the course of action of electromagnetic waves surrounding our life (ionizing radiations, microwaves, ultraviolet light, radio waves) by using short pulse laser.

Dátum: 2015. július 10.

Előadás címe: Fiber Lasers and amplifiers

Előadó: Zoltán Várallyay


We briefly review the operation and types of optical fibers. Nonlinear and dispersive pulse propagations in optical fibers are discussed which both can be advantageous or disadvantageous for some applications. Keeping in mind these properties and using rear-earth doped optical fibers one can build fiber lasers which regarding the arrangement and basic operation of them are very similar to solid state lasers however they are considered environmentally more stable and financially more rewarding. The question is whether we can reach similar power levels and similar short pulse widths (few-cycle femtosecond laser pulses) from these fiber light sources? The presentation is aiming to show recent efforts reaching these goals which seem to be successful since the High Repetition Rate laser system which are going to be built for the Extreme Light Infrastructure - Attosecond Light Pulse Source (ELI-ALPS) in Hungary is based on this technology.

Dátum: 2015. június 19.

Előadás címe: Recording Real Time “µm-fs” Movies Inside Laser Generated Extreme Plasmas

Előadó: Subhendu Kahaly


Visible matter predominantly exists in the form of plasma, be it in the interior of the stars, magnetically confined devices or intense laser generated. Laser induced plasmas can be extremely dense (ne ~ 1017-1025 cm-3), hot (Te ~ 0.1-100 keV) and short-lived (~ fs-ns). The laser produced laboratory plasmas can be over-dense (Solid Plasma Mirrors1 or special Gas-jets2) or under-dense (Gas-jets) and are home to world’s largest magnetic fields, smallest particle accelerators and tiniest sources of the shortest known attosecond XUV pulses. They also form test-beds for studying laboratory astrophysics and exotic plasma science.

In this seminar I would discuss how astrophysical conditions3,4,5 can be recreated inside the laboratory elucidating the metrology schemes that lets us probe these systems. I would present a glimpse of how space-time resolved movies in µm-fs domain can unravel rich dynamics of electrons in relativistic laser plasma accelerators4,5.


1. H. Vincenti, S. Monchocé, S. Kahaly, Ph. Martin and F. Quéré“Optical properties of relativistic plasma mirrors” - Nature Communications5, 3403 (2014)

2. F. Sylla, M. Veltcheva, S. Kahaly, A. Flacco and V. Malka “Development and characterizarion of very dense submillemetric gas jets for laser plasma interaction” - Review of Scientific Instruments 83, 033507 (2012)

3. F. Sylla, A. Flacco, S. Kahaly, M. Veltcheva, E. d’Humières, I. Andriyash, V. Tikhonchuk and V. Malka “Short intense laser pulse collapse in near-critical plasma ”- Physical review letters 110, 085001 (2013)

4. S. Kahaly, S. Mondal,G. Ravindra Kumar, S. Sengupta, A. Das and P.K. Kaw “Polarimetric detection of laser induced ultrashort magnetic pulses in overdense plasma” - Physics of Plasmas 16, 043114 (2009)

5. A. Flacco, J. Vieira, A. Lifschitz, F. Sylla, S. Kahaly, M. Veltcheva, L. O. Silva and V. Malka “Persistence of magnetic driven by relativistic electrons in a plasma”- Nature Physics 11, 409-413 (2015)

Dátum: 2015. június 12.

Előadás címe: Safety System of ELI-ALPS

Előadó: Tamara Kecskés


The active, passive elements of the radiation protection system, protocols and the personnel safety system of ELI-ALPS will be described in this presentation detailed.
Laser safety includes the safe design, use and implementation of lasers to minimize the risk of laser accidents, especially those involving eye injuries. Radiation protection aims at reducing human exposure to radiation through the proper management and disposal of all radioactive materials utilized in research activities. In both cases - radiation protection and laser safety - policies and procedures will assist in the safe handling of radioactive materials.
During the implementation and operation phases the Safety and Security Group is responsible for providing and maintaining safe and healthy working conditions, equipment and systems of work for its staff, together with effective management of health and safety risks including effective information, instruction, training and supervision. In accordance with national law and legislation our group is responsible for the health, safety and welfare of all employees and for the health and safety of users/visitors to ELI-ALPS sites and others who may be affected by ELI-ALPS’s activities. The responsible and professional management of arising hazards (laser, radiation, biological, chemical,electrical, etc.) makes the ELI-ALPS a safe place to work for staff, contractors, visitors and facility users. The safety professionals of the group are responsible for ensuring that there are simple and effective safety systems for managers and staff to employ - maintaining and/or improving safety performance.

Dátum: 2015. május 22.

Előadás címe: Optical tunneling and quantum entanglement

Előadó: Attila Czirják


Optical tunneling [1] has a fundamental role in attosecond physics [2]: a sufficiently strong low frequency laser pulse enables an electron to tunnel out from its atomic bound state into the continuum, which is the first step of the very successful three-step model [3] underlying our understanding of HHG [4]. Recent progress in experimental techniques opened the possibility of measuring quantum processes with attosecond time resolution [5]. This new quantum metrology demands more theoretical knowledge about fundamental features of tunneling [6], e.g. tunneling time and exit momentum.
The above fundamental process also creates an entangled pair of quantum particles, which opens the possibility to control the pair entanglement by the features of the generating laser pulse [7].
We address the above problems by simulating a hydrogen atom interacting with a linearly polarized few-cycle laser pulse in 3 spatial dimensions, and we compare our new results with earlier works based on different 1D atomic model potentials [8, 9], using quantum phase space methods [8-10].

[1] L.V. Keldysh, Sov. Phys.- JETP 20 (1965) 1307–14
[2] F. Krausz, M. Ivanov, Rev. Mod. Phys. 81 (2009) 163
[3] P.B. Corkum, Phys. Rev. Lett. 71 (1993) 1994
[4] M. Lewenstein et al., Phys. Rev. A 49 (1994) 2117
[5] M. Uiberacker et al., Nature 446 (2007) 627
[6] A.N. Pfeiffer et al., Phys. Rev. Lett. 109 (2012) 083002
[7] M.G. Benedict, et al., J. Phys. A: Math. Theor. 45 (2012) 085304
[8] A. Czirjak, et al., Opt. Com. 179 (2000) 29-38;
[9] A. Czirjak, et al., Phys. Scr. T153 (2013) 014013
[10] D.M. Heim et al., Phys. Lett. A 377 (2013) 1822–1825

Dátum: 2015. május 15.

Előadás címe: Ultrafast spectroscopy on bacteriorhodopsin and coenzymes

Előadó: Géza Groma (Hungarian Academy of Sciences, Biological Research Centre, Biophysical Institute, Szeged)


Bacteriorhodopsin – the single protein in the purple membrane of Halobacterium salinarum – utilizes light energy for building proton gradient across the membrane. The electrochemical potential created by this way is then used by ATPases for the synthesis of ATP molecule. The first part of my talk will focus on the characterization of the early processes of the energy transduction by femtosecond spectroscopy. We found that the purple membranes can be macroscopically oriented, leading to a non-centrosymmetric sample of high second-order susceptibility. The corresponding resonant optical rectification process is observable in the form of coherent emission in the mid-infrared and THz region. Monitoring these radiations makes possible to follow the time evolution of the light-induced intramolecular electron translocation in the retinal chromophore, as well as that of the accompanying coherent nuclear vibrations and the subsequent early proton transport processes. In the second part of my talk I will outline the capabilities of our laboratory for measuring and analysing time-resolved fluorescence kinetics in the 100 fs – 10 ns time range, and show our results in the characterization of the different conformational states of coenzymes FAD and NADH.

Dátum: 2015. május 14.

Előadás címe: Attosecond Physics in the Condensed Phase: From the Bloch Oscillator to Electronic Dephasing in Solids

Előadó: Eleftherios Goulielmakis, Max-Planck (Institut für Quantenoptik, Garching, Germany)


With the fastest optical1,2,3 and soft x-ray fields4 as a part of its repertoire, attosecond physics has opened up new avenues for exploring ultrafast electronic processes in atoms5,6,molecules7, surfaces8 or nanostructures9. I will discuss how recent efforts towards advancement of the toolbox of attosecond science allow, for the first time, the exploration and control of fundamental electronic phenomena in condensed matter.Electron motion in bulk media, driven by intense, precise-sculpted, optical fields gives rise to controllable electric currents, the frequency of which extends to the multi-ten-Petahertz range9, advancing lightwave electronics10 to new realms of speed and precision.Coherent extreme ultraviolet radiation emerging in these coherent charge oscillations9 offers direct insight into structural and dynamical properties of the underlying medium, previously inaccessible to conventional solid-state spectroscopies. By endowing essential x-ray spectroscopies of solids with attosecond temporal resolution, optical half-optical cycle fields, combined with extreme ultraviolet pulses, offer, for the first time, access into the attosecond dephasing of electronic excitation of highly-correlated, condensed phase electronic systems11. We anticipate these new capabilities to result in far reaching implications to fundamental and applied, electronic and photonic sciences.
[1] GoulielmakisE. et al., Science 305, 1267 (2004) [2] WirthA. et al., Science 334, 195 (2011). [3] Hassan M. Thet al., Naturesubmitted ( 2014) [4] al., Science 320, 1614 (2008).[5] GoulielmakisE. et al., Nature 466, 739 (2010). [6] Kienberger R. et al., Nature 427, 817 (2004) [6], Smirnova et. al, Nature 460,972(2009) [7] Cavalieri A L et al., Nature 449,1029 (2007) [8]Krueger M et al. Nature 475,78 (2011) [9] Luu T.T. et al., Nature Submitted (2014). [10] Goulielmakis E. et al., Science 317, 769 (2007). [11] Moulet A. et al., in preparation (2014).

Dátum: 2015. május 8.

Előadás címe: Surface excitons on ZnO

Előadó: Sergei Kühn


Most semiconductors with a direct band gap exhibit strong excitonic features in their optical absorption and photoluminescence spectra. Excitons, which are correlated electron-hole pairs, can exists as freely moving or localized quasiparticles. The energetic position and shape of their excitonic resonances hold clues about the specific type of the exciton and its nanoscopic environment. Zinc oxide (ZnO) has received much attention because its wide bandgap (3.5 eV) and high exciton binding energy (60 meV) make it a promising candidate for short-wavelength optoelectronic applications. The study of ZnO nanostructures revealed a strong signature of excitons that are localized near the semiconductors surface, the so-called surface exciton (SX). We investigate the SX on a single-crystalline ZnO surface using a high-resolution near-field scanning optical microscope (NSOM) at a temperature of 4 K. The results are discussed in terms of the physics and technological applications of hybrid materials that consist of an inorganic and an organic semiconductor material. In the second part of the seminar I will briefly report about my recent secondment to FORTH-IESL, the developer’s site of the GHHG user beam line driven by the Sylos laser at ELI-ALPS.

Dátum: 2015. április 24.

Előadás címe: Scientific Computing at ELI-ALPS

Előadó: Péter Szász


The Scientific Computing Group (a.k.a. SciComp) is part of the Scientific Engineering Division of ELI-ALPS with various responsibilities. On the one hand SciComp takes its part in the construction of the ELI-ALPS by defining and developing the scientific computing aspects of the future user facility, on the other hand provides services and support in the current phase for the scientist and researcher colleagues in connection with scientific software and scientific programming tasks.
We will present the current state of each area. As part of the presentation we go through the list of the available software licences and open source tools and also present examples of collaboration between SciComp and researcher teams.

Dátum: 2015. április 17.

Előadás címe: Electron Acceleration by a Chirped Laser Pulse in Underdense Plasmas

Előadó: Mihály Pocsai (HHAS Wigner Research Centre of Physics, Dept. of High-energy Physics)


An effective theory of laser–plasma based particle acceleration is presented. Here we treated the plasma as a continuous medium with an index of refraction nm in which a single electron propagates. Because of the simplicity of this model, we did not need to perform PIC simulations in order to study the properties of the electron acceleration. We studied the properties of the electron motion due to the Lorentz force and the relativistic equations of motion were numerically solved and analysed. We compared our results to PIC simulations and experimental data. As a recent feature, we improved our model for bichromatic laser fields.

Dátum: 2015. április 17.

Előadás címe: Laser Assisted Proton Collision on Light Nuclei at Moderate Energies

Előadó: Imre Barna


We present analytic angular differential cross section model for laser assisted proton nucleonscattering on a Woods-Saxon optical potential where the nth-order photon absorption is taken intoaccount simultaneously. As a physical example we calculate cross sections for proton-12C collisionat 49 MeV in the laboratory frame where the laser intensity is in the range of 107-1021 W/cm2 atoptical frequencies. The upper intensity limit is slightly below the relativistic regime. As a recent feature we perform calculations for bichromatic laser fields as well.

Dátum: 2015. április 10.

Előadás címe: Enhancement and shaping of the amplification bandwidth in OPA through implementation of multibeam pumping

Előadó: Ádám Börzsönyi


Within the frame of ELI-ALPS laser R&D projects, I visited the Vilnius Universtity Laser Research Center (VU LRC), where the sub-task NLO 3.5 is being implemented. My talk will summarize the progress of this research project. Coherent and incoherent combining is a relatively widely used approach by developers of semiconductor or fiber lasers trying to obtain higher radiation brightness or simply power total power from the aforementioned light sources. On the other hand, the technique of coherent combining has not gained a broad recognition in nonlinear optics yet. An example of coherent combining is multibeam pumped optical parametric amplification which is a method of energy transfer to a single signal beam from more than one pump sources. VU LRC pioneered experiments on multibeam pumping starting from early applications to nanosecond optical parametric oscillators and continuing on various different setups, including amplification of broadband chirped pulses. The planned research is aimed at the generation of broadband chirped laser pulses in the infrared (IR) region above 2 um wavelength and its further parametric amplification by utilizing two pump beams with the emphasis on enhancement and shaping of the signal spectrum.

Dátum: 2015. április 10.

Előadás címe: Report on development of a thin disk Yb:YAG regenerative amplifier for pumping OPCPA systems

Előadó: János Bohus


Yb:YAG as a laser gain material has the advantage of very high quantum efficiency (~91%) therefore low heat generation when pumped with diodes at 940nm, high absorption bandwidth (~10nm), therefore low requirements at the pump diodes, high heat conduction and stress resistance, long upper state lifetime (~1ms) and high emission bandwidth (~6nm). Disk lasers are ideally suited for large average powers as well as high peak powers combined with high beam quality at low demand on pump diode brightness. The seminar reports on progress of development of a thin disk amplifier at TRUMPF Scientific Lasers.

Dátum: 2015. március 27.

Előadás címe: Micromanaging laser-plasma interactions for fast accelerator science

Előadó: Nicholas Matlis (Lawrence Berkeley National Laboratory, Acceleration and Fusion Research Division)


Laser plasma accelerators (LPAs) hold great promise as ultra-compact electron sources because of their high acceleration gradients (~GeV/cm) and flexible format, but have yet to gain wide-spread acceptance due to limitations in their tunability and stability. These limitations, caused by the fluid nature of the accelerator formation, have required the development of sophisticated new techniques tailored to manage the microscopic dynamics of the laser-plasma interaction. This talk will highlight recent work aimed at addressing the unique control challenges of this accelerator format, including the use of multiple-pulse collisions to trigger electron injection, the use of tomography to see through walls, the use of spectroscopic imaging to track gas-plume and laser evolution and the use of chirped-pulse interferometry to resolve wake-induced Raman shifts. These methods provide a tremendous wealth of in-situ, shot-by-shot information from within the accelerator, enabling control of and shining new light on what has previously been a black box accessible primarily by simulation.

Dátum: 2015. február 24.

Előadás címe: Scientific Computing at ELI-ALPS

Előadó: Péter Szász


The Scientific Computing Group (a.k.a. SciComp) is part of the Scientific Engineering Division of ELI-ALPS with various responsibilities. On the one hand SciComp takes its part in the construction of the ELI-ALPS by defining and developing the scientific computing aspects of the future user facility, on the other hand provides services and support in the current phase for the scientist and researcher colleagues in connection with scientific software and scientific programming tasks.
We will present the current state of each area. As part of the presentation we go through the list of the available software licences and open source tools and also present examples of collaboration between SciComp and researcher teams.

Dátum: 2015. február 23.

Előadás címe: The Salamanca project

Előadó: Luca Volpe (CLPU, Salamanca)



Dátum: 2015. február 13.

Előadás címe: Linear interferometric tools for ultrafast pulse diagnostics

Előadó: Ádám Börzsönyi


Spatiotemporal compression of ultrashort pulses is one of the key issues of chirped pulse amplification (CPA), the most common method to achieve high intensity laser beams. Successful shaping of the temporal envelope and recombination of the spectral components of the broadband pulses need careful alignment of the stretcher-compressor stages. Several diagnostic techniques have been developed so far for the characterization of ultrashort pulses. Some of these methods utilize nonlinear optical processes, while others based on purely linear optics, in most cases, combined with spectrally resolving device.
In this seminar I provide a review on the capabilities and limitations of the latter category of the ultrafast diagnostic methods. I give a general description on the background of spectrally resolved linear interferometry and demonstrate various schematic experimental layouts for the detection of material dispersion, angular dispersion and carrier-envelope phase drift. Precision estimations and discussion of potential applications are also provided.

Dátum: 2015. február 4.

Előadás címe: Future perspective of ELI

Előadó: Wolfgang Sandner (ELI-DC)



Dátum: 2015. január 30.

Előadás címe: Crystals and lasers

Előadó: Krisztián Lengyel (Institute for Solid State Physics and Opics, Wigner RCP of the H.A.S.)


One of the great scientific projects nowadays is the ELI with many possibilities for laser physics experiments in the future. The operation of devices in these plans is usually based on an optical crystal. In this lecture the growth, preparation and qualification of non-linear optical crystals produced in the Crystalphysics Group of Wigner Research Centre and having important laser applications will be shown. First, three kinds of growth methods and different technics to investigate the composition and homogeneity of bulk crystals will be described. Specific requirements of applications, in particular acousto-optic modulator, harmonic generation and THz generation, will be discussed together with their consequencies for crystal growth and preparation.

Dátum: 2015. január 23.

Előadás címe: Notes on the notion and description of phase in quantum optics

Előadó: Sándor Varró (ELI ALPS Elméleti és szimulációs csoport)


We discuss the old problem of the quantum phase of an oscillator, which may represent for instance the phase of a quantized mode of the radiation field. After reviewing the main approaches have so far been applied to solve this problem, we shall offer a new solution. Our method is based on a new ‘polar decomposition’ of the quantum amplitude of the field components. With the help of this decomposition we have defined an analogon of the quantum saw-toothphase operator [1]. In the frame of the present approach a generalized spectral decomposition of the phase operator and projectors can be derived in a natural way, and they can be expressed by dyads of SU(1,1) coherent states [2]. Besides, we have found that these new sampling states (generalized projectors) for phase measurements can be generated by an experimentally realizable nonlinear interaction whose coupling strength depends on the intensity. The possible extension of our method to a multimode description may be useful in studying the quantum phase properties of extreme radiation fields, like few–cycle or attosecond light pulses.

Dátum: 2015. január 16.

Előadás címe: The Scientific Engineering Division

Előadó: Sándor Brockhauser


The Scientific Engineering Division (SED) is responsible for providing engineering and technician support for in-house and external researchers as well as user groups during the implementation and operation phases of ELI-ALPS research facility. The long term goal is to built safely and robustly usable beamlines which will offer possibilities to be carried out unique scientific experiments. In the implementation phase, SED has responsibilities like following the building construction, design Beam Transport system parts, following LaSo/SeSo procurements with providing engineering support, working on the integration of LaSo-s, SeSo-s and End Stations, elaborating the Personal Safety System and other safety rules, establish the electrical, mechanical and optical workshops. In the operational phase SED will provide engineering support for each experiment such as preparatory discussions and design with user groups, manufacturing of unique items or installation of experiments.

Dátum: 2015. január 9.

Előadás címe: Laser ion acceleration in plasmas

Előadó: Ashutosh Sharma


Laser acceleration of ions from both solid and gaseous target attracts a great attention because of its potential medical applications including the hadron therapy. The recent development of ELI-ALPS facility which will host the laser system capable of generating ultra-short pulses in the multiterawatt or even petawatt power range at high repetition rate, which is crucial for the investigation of new regimes of laser-matter interactions, especially laser proton acceleration. The most stable and well understood mechanism is the TNSA (Target Normal Sheath Acceleration), which usually requires long pulse duration in order to reach high cut-off energy. Since at ELI-ALPS the short pulses are in the center of interest, we have to consider different mechanisms, where the RPDA (Radiation Pressure Dominant Acceleration) is the driving process. The schemes of interest are the collision-less Shock Wave Acceleration and Magnetic Vortex Ion Acceleration, which is more efficient in near-critical density plasma.

Dátum: 2014. december 5.

Előadás címe: Building a Better Nanoparticle

Előadó: Viktor Chikán (Kansas State University, Dept. of Chemistry)


Semiconductor quantum dots exhibit fascinating and important physical and chemical properties that can hold the potential to play crucial role in transforming the photovoltaic industry, creating new business opportunities and producing electricity to address the increasing global energy needs. Producing relatively efficient solar cells from quantum dots has been already demonstrated by many research groups. An important goal is to better equip these quantum dots for photovoltaic cells by controlling their electrical properties via chemical doping. Prof. Chikan research focuses on the synthesis and optical characterization of colloidal nanoparticles. The research talk will address the challenge of doping of colloidal semiconductor particles for the purpose of improving electrical properties of these particles! Prof. Chikan has an expertise on wide variety of spectroscopic techniques (terahertz, ultrafast laser experiments, and single particle fluorescence spectroscopy) to characterize extrinsic and intrinsic defects formation in colloidal doped CdSe quantum dots and nanorod structures.

Dátum: 2014. november 28.

Előadás címe: Fully fiber integrated all-normal dispersion ring oscillator

Előadó: András Drozdy


Passively mode-locked fiber oscillators are widely used sources where ultrashort pulses are required like in applications such as micromachining, nonlinear microscopy, terahertz optics. Although some setups are reported where the laser cavity contains only polarization maintaining (PM) components to improve environmental stability, non-PM setups are still popular as the required parts are less expensive and the achievable pulse duration can be shorter. For self starting and for stable operation all of the non-PM setups need to include polarization controllers otherwise the setups won't start, or can run in unwanted operation regimes such as CW, noise-like or Q-switched. Although in-line polarization controllers are commercially available, not many setups are reported where these components are used for stabilization [1,2,3,4].
At FETI (Furukawa Electric Technology Institute) such a fully fiber integrated all-normal dispersion Yb based fiber oscillator has been built. This presentation is about the oscillator scheme and the experimental characterization of the operating regimes of such a fiber laser oscillator. An attempt to stabilize the operation of the system with the use of an active feedback system is also discussed.

Dátum: 2014. november 21.

Előadás címe: Contribution of the Wigner Research Centre to the CERN AWAKE Proton Wake Field Acceleration Experiment

Előadó: Imre Barna


In our talk we outline the idea of the planned CERN AWAKE experiment which will be similar to the planned ELI particle accelarator experiments. We explain the experimental and theoretical contributions of the Wigner Research Institute which are important for AWAKE.In the end we briefly mention our future plans.

Dátum: 2014. november 14.

Előadás címe: The first prototype of the Integrated Control System

Előadó: Lajos Fülöp


The first prototype of the integrated control system includes hundreds of very simple simulated devices of four laser sources and four secondary sources, which run in a distributed environment. The prototype also provides operator user interfaces to these beamlines. The prototype is based on the TANGO Controls framework that provides the communication interface, the device configuration database and several toolkits for the rapid development of device drivers, user interfaces and other components. The major goal of the prototype is to clarify the requirements and the architecture.

Dátum: 2014. november 11.

Előadás címe: Imaging of high harmonic focal spot (Secondment to Lund from 13 July to 30 August)

Előadó: Farkas Balázs


In this talk the high intensity HHG beamline at Lund Laser Center and first results of XUV spot size imaging will be presented.

Dátum: 2014. október 31.

Előadás címe: Development of Petawatt-vlass CPA laser at the University of Michigan (Solution of several bottleneck problems)

Előadó: Vladimir Chvykov


SThe 0.3-PW short pulse solid-state laser system was developed and investigated in University of Michigan. The world record laser intensity of 2⋅10²² Watt/cm² and the temporal contrast of the record value 1015 were reached. Several new methods for solving bottleneck problems of the CPA lasers were suggested and implemented during the laser construction. Most of them will be presented in this report, among them:
• The method for increasing extracted energy from multipass amplifiers. Method was successfully applied in the other laboratories and allowed to achieve therecord output power 2 PW .
• New optical system for improvement of temporal contrast up to the record value of 1011.
• New method for the alignment of the Petawatt compressor with 10-6 rad accuracy.
• First demonstrated the compression of 30 TW laser pulses from 30 down to 14 fs via spectral broadening by self-phase modulation.

Dátum: 2014. október 17.

Előadás címe: Laser Polarimetry of High Energy Density Plasmas

Előadó: Dániel Papp


Current High Energy Density Plasma Research focuses on several fields, like Inertial Confinement Fusion, properties of Materials under Extreme Conditions, Laboratory Astrophysics, and novel laser-driven photon/particle sources.Proper diagnostics of these plasmas are crucial to understand physical processes and to benchmark numerical codes. Laser probing is widely available, offers good spatial and temporal resolution, and is one of the few methods that can be used to determine magnetic fields present in such plasmas. I will introduce the physics behind laser probing, discuss the methods it can be used (shadowgraphy, interferometry, polarimetry). Two applications of these principles will be presented. The first would be z-pinch generated plasmas probed by ns lasers to determine current distribution within the z-pinch. The second application would be the probing of fs laser-generatedplasmas to determine the temporal evolution of the self-generated magnetic field. Z-pinch experiments were conducted at Nevada Terawatt Facility, Reno, NV, USA. Ultrafast laser experiments were conducted at CELIA, Bordeaux, France.

Dátum: 2014. október 10.

Előadás címe: Mechanical engineering

Előadó: Zoltán Tóth


Mirror mount design, Beamline node design, Polarization rotator equipment design

Dátum: 2014. október 3.

Előadás címe: Possible laser-driven proton acceleration mechanisms at the ELI-ALPS, Hungary

Előadó: Zsolt Lécz


Laser acceleration of ions from both solid and gaseous target attracts a great attention because of its potential usage in many scientific and medical applications, including hadron therapy.The presentation consists of two parts: first a brief summary of the CERN School of Computing is given, and its relevance to the high performance computing at ELI-ALPS is discussed. Secondly several laser ion acceleration mechanisms in plasmas are presented, which could be realized with ultra-short laser pulses provided by the HF laser system of the future ELI-HU facility. The currently investigated Shock Wave Acceleration, driven by the radiation pressure of the laser pulse, is presented in more details. Particle in Cell simulations show promising results, which gives us the confidence for initiating experimental campaign, where this regime can be tested.

Dátum: 2014. szeptember 26.

Előadás címe: Laser-driven fast electron transport in matter and/or plasmas.State of the art from experimental and theoretical point of view

Előadó: Luca Volpe


When high power(> 1 TW) laseris focused on solid targets, the electrons of the target are accelerated to relativistic velocities. The laser-driven electron beam starts to travel into the target transporting and depositing part of the laser energy in the over-dense region of the target.
The electron dynamic into the target depends both on the collisions and onthe electro-magnetic interactions. Electrons lose energy both by collisional and resistive stopping power and they change their divergence viainelastic scattering and magnetic field collimation.
The physics offast electron transport has been studied intensively in the last two decades mainly connected to fast ignition (thick foils) and proton acceleration (thin foils) schemes.
Theoretically the process can be separated in two parts: i) the first (generation) describes the laser-matter interaction and electron generation by neglecting collisions (based on the integration of the Vlasov--Maxwell system i.eParticle in Cell Code), ii) the second (transport) describes the propagation of the relativistic beam in the target with collisions (based on the integration of the Fokker-Plank--Maxwell system i.e kinetic code).
An introduction of the topic will be presented with particular attention to the time fs regime which is relevant for ELI-ALPS. Numerical simulations by using the kinetic code M1areshown.

Dátum: 2014. szeptember 19.

Előadás címe: Electromagneticwake-fields and rectangular waves, generated by strong laser fields on thin plasma layers or on graphene

Előadó: Sándor Varró


The generation of broad-band radiation an short pulses relies on the highly nonlinear processes induced by the intense laser fields [1]. Carrier-envelope phase difference effects [2] are also important concerning short pulses. In the present talk we show that the collective radiation back-reaction of (relativistic) surface currents driven by a laser field can cause extreme nonlinearities and a violent distortion in the scattered radiation. This phenomenon has already been considered by us, for the reflection of laser pulses on thin conducting (plasma) nano-layers [3-4], where the appearance of attosecond pulses and giant quasistatic wakefields has been predicted. We report also on new recent results [5-6], and discuss examples for the temporal behaviour of the reflected signals. In the case of graphene the reflected signal may contain only a radiation reaction term which is proportional with the velocity of the (convection) surface current, if the laser pulse impinges at Brewster angle on a graphene layer. The existence of such a reflectedcomponentcannot come out from the usual Fresnel formulae. Due to the ultrarelativistic kinematics of the electrons, the maximum signal is reached already at the rising part, and this ‘saturation’ causes a sort of ‘relativistic clipping’, which results in a rectangular temporal shape. These rectangular trains (approximating Rademacher functions) may perhaps serve as a clock signal being 100 000 times faster than a 10 gigahertz clock.

Dátum: 2014. szeptember 5.

Előadás címe: Trapping of High Power Laser Pulses for Interaction with Low Density Targets

Előadó: Mohamed Tarek


The design, construction and test of an optical storage devices for trapping a high power laser pulse will be presented in this talk. With the help of these devices, the repetition rate of the used high power laser system can reach the order of 100 MHz and the average power increases by a factor of 25. The aim of the optical devices is to increase the efficiency of using a high power laser pulse in different applications that need high laser repetition rate.