We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,Phys.Plasmas 28,023103(2021)].In a continuation of this nu...We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,Phys.Plasmas 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas jet.Without tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb explosion.When the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are tailored.This forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe beam.The refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma tailoring.Comparison with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas jet.These parameters are in good agreement with those required for CSA.展开更多
Over the last two decades,the importance of fully ionized plasmas for the controlled manipulation of high-power coherent light has increased considerably.Many ideas have been put forward on how to control or change th...Over the last two decades,the importance of fully ionized plasmas for the controlled manipulation of high-power coherent light has increased considerably.Many ideas have been put forward on how to control or change the properties of laser pulses such as their frequency,spectrum,intensity,and polarization.The corresponding interaction with a plasma can take place either in a self-organizing way or by prior tailoring.Considerable work has been done in theoretical studies and in simulations,but at present there is a backlog of demand for experimental veri-fication and the associated detailed characterization of plasma-optical elements.Existing proof-of-principle experiments need to be pushed to higher power levels.There is little doubt that plasmas have huge potential for future use in high-power optics.This introduction to the special issue of Matter and Radiation at Extremes devoted to plasma optics sets the framework,gives a short historical overview,and briefly describes the various articles in this collection.展开更多
Understanding the behavior of matter at extreme pressures of the order of a megabar(Mbar)is essential to gain insight into various physical phenomena at macroscales—the formation of planets,young stars,and the cores ...Understanding the behavior of matter at extreme pressures of the order of a megabar(Mbar)is essential to gain insight into various physical phenomena at macroscales—the formation of planets,young stars,and the cores of super-Earths,and at microscales—damage to ceramic materials and high-pressure plastic transformation and phase transitions in solids.Under dynamic compression of solids up to Mbar pressures,even a solid with high strength exhibits plastic properties,causing the induced shock wave to split in two:an elastic precursor and a plastic shock wave.This phenomenon is described by theoretical models based on indirect measurements of material response.The advent of x-ray free-electron lasers(XFELs)has made it possible to use their ultrashort pulses for direct observations of the propagation of shock waves in solid materials by the method of phase-contrast radiography.However,there is still a lack of comprehensive data for verification of theoretical models of different solids.Here,we present the results of an experiment in which the evolution of the coupled elastic-plastic wave structure in diamond was directly observed and studied with submicrometer spatial resolution,using the unique capabilities of the x-ray free-electron laser(XFEL).The direct measurements allowed,for the first time,the fitting and validation of the 2D failure model for diamond in the range of several Mbar.Our experimental approach opens new possibilities for the direct verification and construction of equations of state of matter in the ultra-high-stress range,which are relevant to solving a variety of problems in high-energy-density physics.展开更多
Advanced X-ray spectroscopic methods provide unique and critical data to study matter under extreme environmental conditions induced by high-intensity and high-energy lasers.The aim of this paper is to contribute to a...Advanced X-ray spectroscopic methods provide unique and critical data to study matter under extreme environmental conditions induced by high-intensity and high-energy lasers.The aim of this paper is to contribute to a contemporary discussion of the role of X-ray spectroscopy in the investigation of radiative properties of strongly coupled,highly correlated,and frequently weakly emissive plasma systems formed in matter irradiated by sub-petawatt and petawatt class lasers.After reviewing the properties of different X-ray crystal spectrometers,high-resolution X-ray diagnostic methods are surveyed with respect to their potential to study plasmainduced and externally induced radiation fields,suprathermal electrons,and strong electromagnetic field effects.Atomic physics in dense plasmas is reviewed with emphasis on non-Maxwellian non-LTE atomic kinetics,quasi-stationary and highly-transient conditions,hollow ion X-ray emission,and field-perturbed atoms and ions.Finally,we discuss the role of X-ray free electron lasers with respect to supplementary investigations of matter under extreme conditions via the use of controlled high-intensity radiation fields.展开更多
Statistical models combined with the local plasma frequency approach applied to the atomic electron density are employed to study the photoionization cross-section for complex atoms.It is demonstrated that the Thomas...Statistical models combined with the local plasma frequency approach applied to the atomic electron density are employed to study the photoionization cross-section for complex atoms.It is demonstrated that the Thomas–Fermi atom provides surprisingly good overall agreement even for complex outer-shell configurations,where quantum mechanical approaches that include electron correlations are exceedingly difficult.Quantum mechanical photoionization calculations are studied with respect to energy and nl quantum number for hydrogen-like and non-hydrogen-like atoms and ions.Ageneralized scaled photoionizationmodel(GSPM)based on the simultaneous introduction of effective charges for non-H-like energies and scaling charges for the reduced energy scale allows the development of analytical formulas for all states nl.Explicit expressions for nl1s,2s,2p,3s,3p,3d,4s,4p,4d,4f,and 5s are obtained.Application to H-like and non-H-like atoms and ions and to neutral atoms demonstrates the universality of the scaled analytical approach including inner-shell photoionization.Likewise,GSPMdescribes the near-threshold behavior and high-energy asymptotes well.Finally,we discuss the various models and the correspondence principle along with experimental data and with respect to a good compromise between generality and precision.The results are also relevant to large-scale integrated light–matter interaction simulations,e.g.,X-ray free-electron laser interactions with matter or photoionization driven by a broadband radiation field such as Planckian radiation.展开更多
On the basis of equations obtained in the framework of second-order quantum-mechanical perturbation theory,the standard approach to the calculation of scattering radiation probability is extended to the case of ultras...On the basis of equations obtained in the framework of second-order quantum-mechanical perturbation theory,the standard approach to the calculation of scattering radiation probability is extended to the case of ultrashort laser pulses.Weinvestigate the mechanism of the appearance of plasmon peaks in the spectrum of the plasma form factor for different parameters of the problem.For the case in which scattering on plasmons dominates over scattering on electron density fluctuations caused by chaotic thermal motion,we derive analytical expressions describing the scattering probability of ultrashort laser pulses on plasmons.Together with this,we obtain a simple expression connecting the frequency of scattered radiation and the energy transmitted from the incident pulse to plasmon,and vice versa.In considering the scattering probability,our emphasis is on the dependence on the pulse duration.Weassess in detail the trends of this dependence for various relations between pulse carrier frequency and plasmon energy.展开更多
The use of plasmas provides a way to overcome the low damage threshold of classical solid-state based optical materials,which is the main limitation encountered in producing and manipulating intense and energetic lase...The use of plasmas provides a way to overcome the low damage threshold of classical solid-state based optical materials,which is the main limitation encountered in producing and manipulating intense and energetic laser pulses.Plasmas can directly amplify or alter the characteristics of ultra-short laser pulses via the three-wave coupling equations for parametric processes.The strong-coupling regime of Brillouin scattering(sc-SBS)is of particular interest:recent progress in this domain is presented here.This includes the role of the global phase in the spatio-temporal evolution of the three-wave coupled equations for backscattering that allows a description of the coupling dynamics and the various stages of amplification from the initial growth to the so-called self-similar regime.The understanding of the phase evolution allows control of the directionality of the energy transfer via the phase relation between the pulses.A scheme that exploits this coupling in order to use the plasma as a wave plate is also suggested.展开更多
In 2020,Matter and Radiation at Extremes(MRE)reached a particularly important milestone when it received its first official impact factor of 2.931,which indicates the high quality of the papers published to date.This ...In 2020,Matter and Radiation at Extremes(MRE)reached a particularly important milestone when it received its first official impact factor of 2.931,which indicates the high quality of the papers published to date.This outstanding success can be attributed to the strong commitment and valuable contributions from all the reviewers.The Editors of MRE wish to express their deepest gratitude to the following individuals who generously provided advice on manuscripts as reviewers for MRE in the year of 2020.展开更多
The theory of photoionization describing the interaction of x-ray free-electron laser(XFEL)pulses and high-harmonic-generated(HHG)radiation is generalized to ultrashort laser pulses,where the concept of the standard i...The theory of photoionization describing the interaction of x-ray free-electron laser(XFEL)pulses and high-harmonic-generated(HHG)radiation is generalized to ultrashort laser pulses,where the concept of the standard ionization probability per unit time in Fermi’s golden rule and in Einstein’s theory breaks down.Numerical calculations carried out in terms of a generalized photoionization probability for the total duration of pulses in the near-threshold regime demonstrate essentially nonlinear behavior,while absolute values may change by orders of magnitude for typical XFEL and HHG pulses.XFEL self-amplified spontaneous emission pulses are analyzed to reveal general features of photoionization for random and regular spikes:the dependences of the nonlinear photoionization probability on carrier frequency and spike duration are very similar,allowing an analytical expectation value approach that is valid even when there is only limited knowledge of random and regular parameters.Numerical simulations carried out for typical parameters demonstrate excellent agreement.展开更多
基金funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No.871124 Laserlab-Europeby Grant No.ANR-17-CE30-0026-Pinnacle from the Agence Nationale de la Recherche.
文摘We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,Phys.Plasmas 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas jet.Without tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb explosion.When the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are tailored.This forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe beam.The refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma tailoring.Comparison with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas jet.These parameters are in good agreement with those required for CSA.
基金support from the Federation Plas@par project and the support of Tremplin 2022 call(Sorbonne University,Science Faculty)support from the Advanced Research Using High Intensity Laser Produced Photons and Particles(ADONIS)Project(No.CZ.02.1.01/0.0/0.0/16_019/0000789)by the High Field Initiative Project(No.CZ.02.1.01/0.0/0.0/15_003/0000449)(HiFI),both from the European Regional Development Fund.
文摘Over the last two decades,the importance of fully ionized plasmas for the controlled manipulation of high-power coherent light has increased considerably.Many ideas have been put forward on how to control or change the properties of laser pulses such as their frequency,spectrum,intensity,and polarization.The corresponding interaction with a plasma can take place either in a self-organizing way or by prior tailoring.Considerable work has been done in theoretical studies and in simulations,but at present there is a backlog of demand for experimental veri-fication and the associated detailed characterization of plasma-optical elements.Existing proof-of-principle experiments need to be pushed to higher power levels.There is little doubt that plasmas have huge potential for future use in high-power optics.This introduction to the special issue of Matter and Radiation at Extremes devoted to plasma optics sets the framework,gives a short historical overview,and briefly describes the various articles in this collection.
基金We thank the technical staff of SACLA for their support during the experiment.The experiment was performed at BL3 of SACLA with the approval of the Japan Synchrotron Radiation Research Institute(Proposal Nos.2021A8004 and 2021B8002).The high-power drive laser installed in SACLA EH5 was developed with the cooperation of Hamamatsu Photonics.The installation of diffractive optical elements to improve the smoothness of the drive laser-pattern was supported by the SACLA Basic Development ProgramThe work was carried out with the financial support of the Russian Federation represented by the Ministry of Science and Higher Education of the Russian Federation(Grant No.075-15-2021-1352)This work was supported by KAKENHI(Grant Nos.17K05729 and 21K03499)from the Japan Society for the Promotion of Science(JSPS).
文摘Understanding the behavior of matter at extreme pressures of the order of a megabar(Mbar)is essential to gain insight into various physical phenomena at macroscales—the formation of planets,young stars,and the cores of super-Earths,and at microscales—damage to ceramic materials and high-pressure plastic transformation and phase transitions in solids.Under dynamic compression of solids up to Mbar pressures,even a solid with high strength exhibits plastic properties,causing the induced shock wave to split in two:an elastic precursor and a plastic shock wave.This phenomenon is described by theoretical models based on indirect measurements of material response.The advent of x-ray free-electron lasers(XFELs)has made it possible to use their ultrashort pulses for direct observations of the propagation of shock waves in solid materials by the method of phase-contrast radiography.However,there is still a lack of comprehensive data for verification of theoretical models of different solids.Here,we present the results of an experiment in which the evolution of the coupled elastic-plastic wave structure in diamond was directly observed and studied with submicrometer spatial resolution,using the unique capabilities of the x-ray free-electron laser(XFEL).The direct measurements allowed,for the first time,the fitting and validation of the 2D failure model for diamond in the range of several Mbar.Our experimental approach opens new possibilities for the direct verification and construction of equations of state of matter in the ultra-high-stress range,which are relevant to solving a variety of problems in high-energy-density physics.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60490281 and 60608003, and the National Basic Research Program of China under Grant No 2007CB815104, and the National High-Tech Research and Development Program of China.
基金One of the authors(O.R.)acknowledges support from the Czech Republic Ministry of Education,Youth and Sports within targeted support of Large Infrastructures,ELI Beamlines Project No.LQ1606 of the National Programme of Sustainability II,and Prague Asterix Laser System Project No.LM2015083.
文摘Advanced X-ray spectroscopic methods provide unique and critical data to study matter under extreme environmental conditions induced by high-intensity and high-energy lasers.The aim of this paper is to contribute to a contemporary discussion of the role of X-ray spectroscopy in the investigation of radiative properties of strongly coupled,highly correlated,and frequently weakly emissive plasma systems formed in matter irradiated by sub-petawatt and petawatt class lasers.After reviewing the properties of different X-ray crystal spectrometers,high-resolution X-ray diagnostic methods are surveyed with respect to their potential to study plasmainduced and externally induced radiation fields,suprathermal electrons,and strong electromagnetic field effects.Atomic physics in dense plasmas is reviewed with emphasis on non-Maxwellian non-LTE atomic kinetics,quasi-stationary and highly-transient conditions,hollow ion X-ray emission,and field-perturbed atoms and ions.Finally,we discuss the role of X-ray free electron lasers with respect to supplementary investigations of matter under extreme conditions via the use of controlled high-intensity radiation fields.
基金The work described here was supported by the Cooperation Agreement between the Sorbonne University,Faculty of Sciences(Pierre and Marie Curie)and the Moscow Institute of Physics and Technology MIPTFinancial support from MIPT in the framework of Grant No.075-02-2019-967 and the 5-top-100 program is greatly acknowledgedThis work has also been supported by the Competitiveness Program of NRNU MEPhI in the framework of the Russian Academic Excellence Project.
文摘Statistical models combined with the local plasma frequency approach applied to the atomic electron density are employed to study the photoionization cross-section for complex atoms.It is demonstrated that the Thomas–Fermi atom provides surprisingly good overall agreement even for complex outer-shell configurations,where quantum mechanical approaches that include electron correlations are exceedingly difficult.Quantum mechanical photoionization calculations are studied with respect to energy and nl quantum number for hydrogen-like and non-hydrogen-like atoms and ions.Ageneralized scaled photoionizationmodel(GSPM)based on the simultaneous introduction of effective charges for non-H-like energies and scaling charges for the reduced energy scale allows the development of analytical formulas for all states nl.Explicit expressions for nl1s,2s,2p,3s,3p,3d,4s,4p,4d,4f,and 5s are obtained.Application to H-like and non-H-like atoms and ions and to neutral atoms demonstrates the universality of the scaled analytical approach including inner-shell photoionization.Likewise,GSPMdescribes the near-threshold behavior and high-energy asymptotes well.Finally,we discuss the various models and the correspondence principle along with experimental data and with respect to a good compromise between generality and precision.The results are also relevant to large-scale integrated light–matter interaction simulations,e.g.,X-ray free-electron laser interactions with matter or photoionization driven by a broadband radiation field such as Planckian radiation.
基金funded by MIPT in the framework of the 5-Top-100 Programsupported by RFBR,Project No.19-32-90016.
文摘On the basis of equations obtained in the framework of second-order quantum-mechanical perturbation theory,the standard approach to the calculation of scattering radiation probability is extended to the case of ultrashort laser pulses.Weinvestigate the mechanism of the appearance of plasmon peaks in the spectrum of the plasma form factor for different parameters of the problem.For the case in which scattering on plasmons dominates over scattering on electron density fluctuations caused by chaotic thermal motion,we derive analytical expressions describing the scattering probability of ultrashort laser pulses on plasmons.Together with this,we obtain a simple expression connecting the frequency of scattered radiation and the energy transmitted from the incident pulse to plasmon,and vice versa.In considering the scattering probability,our emphasis is on the dependence on the pulse duration.Weassess in detail the trends of this dependence for various relations between pulse carrier frequency and plasmon energy.
基金This work has been done within the LABEX Plas@par project,and received financial state aid managed by the Agence Nationale de la Recherche,as part of the program“Investissements d’avenir”under the reference ANR-11-IDEX-0004-02.H.P.acknowledges the funding from China Scholarship Council.S.W.was supported by the project Advanced research using high intensity laser produced photons and particles(ADONIS)(CZ.02.1.01/0.0/0.0/16_019/0000789)from the European Regional Development Fund and by the project High Field Initiative(HiFI)(CZ.02.1.01/0.0/0.0/15_003/0000449)from the European Regional Development Fund.
文摘The use of plasmas provides a way to overcome the low damage threshold of classical solid-state based optical materials,which is the main limitation encountered in producing and manipulating intense and energetic laser pulses.Plasmas can directly amplify or alter the characteristics of ultra-short laser pulses via the three-wave coupling equations for parametric processes.The strong-coupling regime of Brillouin scattering(sc-SBS)is of particular interest:recent progress in this domain is presented here.This includes the role of the global phase in the spatio-temporal evolution of the three-wave coupled equations for backscattering that allows a description of the coupling dynamics and the various stages of amplification from the initial growth to the so-called self-similar regime.The understanding of the phase evolution allows control of the directionality of the energy transfer via the phase relation between the pulses.A scheme that exploits this coupling in order to use the plasma as a wave plate is also suggested.
文摘In 2020,Matter and Radiation at Extremes(MRE)reached a particularly important milestone when it received its first official impact factor of 2.931,which indicates the high quality of the papers published to date.This outstanding success can be attributed to the strong commitment and valuable contributions from all the reviewers.The Editors of MRE wish to express their deepest gratitude to the following individuals who generously provided advice on manuscripts as reviewers for MRE in the year of 2020.
基金funded by RFBR Grant No.19-32-90016,Ecole Polytechnique,the Cooperation Agreement between the Sorbonne University and MIPT,and the MIPT 5-top-100 programsupported by the Competitiveness Program of NRNU MEPhI in the framework of the Russian Academic Excellence Project.
文摘The theory of photoionization describing the interaction of x-ray free-electron laser(XFEL)pulses and high-harmonic-generated(HHG)radiation is generalized to ultrashort laser pulses,where the concept of the standard ionization probability per unit time in Fermi’s golden rule and in Einstein’s theory breaks down.Numerical calculations carried out in terms of a generalized photoionization probability for the total duration of pulses in the near-threshold regime demonstrate essentially nonlinear behavior,while absolute values may change by orders of magnitude for typical XFEL and HHG pulses.XFEL self-amplified spontaneous emission pulses are analyzed to reveal general features of photoionization for random and regular spikes:the dependences of the nonlinear photoionization probability on carrier frequency and spike duration are very similar,allowing an analytical expectation value approach that is valid even when there is only limited knowledge of random and regular parameters.Numerical simulations carried out for typical parameters demonstrate excellent agreement.
