Publications

2022 | 2021 | 2020 | 2019

Sont listées ci-dessous, par année, les publications figurant dans l'archive ouverte HAL.

2025

Shock compression of FeOOH and implications for iron-water interactions in super-earth magma oceans
- Zhang Yanyao
- Bali Komal
- Dorn Caroline
- Ravasio Alessandra
- Yang Hong
- Pandolfi Silvia
- Chen Amanda J
- Wei Xuehui
- Libon Lélia
- Che Qijun
- Zheng Donghao
- Boulard Eglantine
- Benuzzi-Mounaix Alessandra
- Lee Hae Ja
- Galtier Eric
- Czapla Nicholas A
- Sokaras Dimosthenis
- Alonso-Mori Roberto
- Gleason Arianna E
- Shim Sang Heon
- Morard Guillaume
- Mao Wendy L
Nature Communications, Nature Publishing Group, 2025, 17 (1), pp.1085. Iron(Fe)-water reactions in a magma ocean can influence water storage and density of planets. These reactions can form Fe-O-H phases, whose density, melting, and electronic properties at planetary interior conditions are important for informing planetary models. Here, we study natural goethite (α-FeOOH) that is shock-compressed along its principal Hugoniot. Analysis of our velocity interferometer system for any reflector (VISAR) results extends the equation of state to over 800 GPa. X-ray diffraction and VISAR reflectivity results indicate the onset of melting occurs at ~95 GPa with complete melting by 166 GPa, which may be relevant to low seismic velocity anomalies observed above the core-mantle boundary. Analysis of X-ray emission spectroscopy results up to 285 GPa shows the spin crossover of Fe, with dominantly low spin Fe above ~265 GPa in the melt, supporting formation of dense basal magma oceans in terrestrial planets. Using our measured FeOOH densities, we model planetary interiors up to 10 Earth masses. Assuming FeOOH forms via ironwater reactions, the radius decreases by up to 28%, while the density increases by up to 165% compared to the unreacted case, providing an avenue to investigate water storage and evolution in super-Earths and sub-Neptunes. (10.1038/s41467-025-67845-8)
DOI : 10.1038/s41467-025-67845-8
Laser-produced magnetized plasmas : heat transport and blast waves
- Triantafyllidis Angelos
, 2025. Magnetic fields are ubiquitous in high-energy-density physics. Whether externally imposed or self-generated, they profoundly alter plasma properties at all scales. For example, they reduce the mobility of charged particles and shape supernova remnants, playing a central role both in the laboratory and the Universe. In this thesis, their effects on heat transport and collisional blast wave structure are investigated experimentally within the framework of inertial confinement fusion (ICF) and laboratory astrophysics.In the first part, magnetized heat transport in laser-produced plasmas is studied using a platform capable of generating fields up to 20 T. The plasma conditions are characterized by a full suite of diagnostics, including temporally and spatially resolved Thomson scattering. Our results provide direct evidence of heat-flux inhibition and preheat suppression induced by the applied magnetic field, which causes a significant temperature increase. The measured electron velocity distribution function is distinctly non-Maxwellian and strongly associated with inverse bremsstrahlung heating.In the second part of this thesis, the experimental platform and diagnostics are repurposed to demonstrate that even modest magnetic fields can affect the blast wave structure. When applied perpendicular to their direction of propagation, the blast waves deviate from the Sedov-Taylor solution, and energy is dissipated along the shock front due to resistive effects. A parallel field, on the other hand, channels the plasma, forming a jet-like structure. For this experiment, a Stark-Zeeman diagnostic is developed that, when coupled with the PPPB code, can retrieve plasma conditions and magnetic field characteristics in a non-intrusive manner.Our findings suggest that magnetic fields of this magnitude could improve ICF schemes by raising fuel temperatures and reducing preheating. They also provide an experimental benchmark for studying magnetized blast waves, thereby forming a basis for interpreting the morphology of their astrophysical counterparts. (10.70675/b91bbcdbz05c0z4fbaza0c4z9f73e8f0f79f)
DOI : 10.70675/b91bbcdbz05c0z4fbaza0c4z9f73e8f0f79f
Electromagnetic Showers for Laboratory Pair Plasma Generation : a Kinetic Perspective
- Pouyez Mattys
, 2025. When a high-energy electron or positron interacts with a strong external field, a part of its energy is converted into a photon through radiation reactions. The high-energy photons interacting with the field can convert all its energy to an electron-positron pair. The combination of these two processes leads to a cascade of secondary particles, electrons, positrons, and photons, also known as an Electromagnetic Shower (EMS).With several petawatt laser facilities and the long-standing objective to generate a plasma of electron-positrons in the laboratory, EMS has become one of the most promising pathways to this goal. With this thesis, we aim to describe the properties of the EMS seeded by high-energy photons or leptons in an atomic or strong electromagnetic field. Despite important progress in understanding the shower properties emerging from Strong-Field Quantum ElectroDynamic (SF-QED) interaction, no study provides an exact and handy solution for the number of pairs, particle spectrum and electron-positron density generated during such interaction. In this thesis, we first revisit the historical theoretical approaches that describe showers: The pioneering model proposed by Heitler [Heitler (1984)] provides an intuitive picture and the elegant solution of the kinetic equations using the Mellin transform for the particle spectra [Landau and Rumer (1938); Akhiezer et al. (1994)], providing a coherent description of the shower. However, these models fail to accurately describe particle spectra and pair multiplicities across all regimes, in particular in both small and long interactions. To overcome these limitations, we develop a new framework applicable to any homogeneous environment (constant magnetic field or homogeneous atomic medium). The shower description is reformulated in terms of successive generations of pair creation and photon emission. Starting from the kinetic equations, we derive explicit analytical expressions with broad generality for the shower multiplicity and particle spectra in what we define as the short-time (before the incident particle has cooled down) and long-time (after the incident particle's energy is exhausted) regimes. We show that this methodology can be extended to realistic scenarios of interest for today's experiments. In the case of electron beam-matter interactions, where the photon emission is induced by the Bremsstrahlung process and the pair creation by the Bethe-Heitler process, we derived analytical expressions for pair yields, jet densities, and divergence, validated against Geant4 simulations [Agostinelli et al. (2003)]. These results allow us to identify the optimal conditions for laboratory pair plasma production. Subsequently, we apply the method to EMS in strong electromagnetic fields where the non-linear Compton Scattering and non-linear Breit-Wheeler processes are responsible for the photon and pair production. We investigate both electron beam-beam collisions and laser-electron beam interactions, obtaining simple explicit scaling laws for pair production that agree with Particle-In-Cell (PIC) simulations. We further analyse the pair density to identify the role of the different parameters on the pair plasma production. Finally, we develop a semi-analytical model that incorporates the temporal and spatial structure of a realistic laser pulse. This model, benchmarked against PIC simulations, shows that shower multiplicities of up to 15 can be achieved in future experiments. It provides predictive guidelines for optimising seeding strategies, laser pulse parameters, and beam configurations. Altogether, this work establishes a general theoretical framework for electromagnetic showers in matter and strong fields, validated against simulations and applicable to experimental designs at upcoming multi-petawatt laser facilities. The results hold relevance for laboratory astrophysics, particle physics instrumentation, and the exploration of strong-field QED processes.
Roadmap for warm dense matter physics
- Vorberger Jan
- Graziani Frank
- Riley David
- Baczewski Andrew
- Baraffe Isabelle
- Bethkenhagen Mandy
- Blouin Simon
- Böhme Maximilian
- Bonitz Michael
- Bussmann Michael
- Casner Alexis
- Cayzac Witold
- Celliers Peter
- Chabrier Gilles
- Chamel Nicolas
- Chapman Dave
- Chen Mohan
- Clérouin Jean
- Collins Gilbert
- Coppari Federica
- Döppner Tilo
- Dornheim Tobias
- Fletcher Luke
- Gericke Dirk
- Glenzer Siegfried
- Goncharov Alexander
- Gregori Gianluca
- Hamel Sebastien
- Hansen Stephanie
- Hartley Nicholas
- Hu Suxing
- Hurricane Omar
- Karasiev Valentin
- Kas Joshua
- Kettle Brendan
- Kluge Thomas
- Knudson Marcus
- Kononov Alina
- Á Zuzana Konôpkov
- Kraus Dominik
- Kritcher Andrea
- Malko Sophia
- Massacrier Gérard
- Militzer Burkhard
- Moldabekov Zhandos
- Murillo Michael
- Nagler Bob
- Nettelmann Nadine
- Neumayer Paul
- Ofori-Okai Benjamin
- Oleynik Ivan
- Preising Martin
- Pribram-Jones Aurora
- Ramazanov Tlekkabul
- Ravasio Alessandra
- Redmer Ronald
- Rethfeld Baerbel
- Robinson Alex
- Röpke Gerd
- Soubiran François
- Starrett Charles
- Steinle-Neumann Gerd
- Sterne Phillip
- Tanaka Shigenori
- Thompson Aidan
- Trickey Samuel
- Vinci Tommaso
- Vinko Sam
- Wang Lei
- White Alexander
- White Thomas
- Zastrau Ulf
- Zurek Eva
- Tolias Panagiotis
, 2025. This roadmap presents the state-of-the-art, current challenges and near future developments anticipated in the thriving field of warm dense matter physics. Originating from strongly coupled plasma physics, high pressure physics and high energy density science, the warm dense matter physics community has recently taken a giant leap forward. This is due to spectacular developments in laser technology, diagnostic capabilities, and computer simulation techniques. Only in the last decade has it become possible to perform accurate enough simulations \& experiments to truly verify theoretical results as well as to reliably design experiments based on predictions. Consequently, this roadmap discusses recent developments and contemporary challenges that are faced by theoretical methods, and experimental techniques needed to create and diagnose warm dense matter. A large part of this roadmap is dedicated to specific warm dense matter systems and applications in astrophysics, inertial confinement fusion and novel material synthesis. (10.48550/arXiv.2505.02494)
DOI : 10.48550/arXiv.2505.02494
Dual quantum locking: Dynamic coupling of hydrogen and water sublattices in hydrogen filled ice
- Renaud Loan
- Poreba Tomasz
- Di Cataldo Simone
- Nicholls Alasdair
- Andriambariarijaona Léon
- Rescigno Maria
- Gaal Richard
- Casula Michele
- Saitta A. Marco
- Bove Livia Eleonora
, 2025. Hydrogen hydrates (HH) are a unique class of materials composed of hydrogen molecules confined within crystalline water frameworks. Among their multiple phases, the filled ice structures, particularly the cubic C2 phase, exhibit exceptionally strong host-guest interactions due to ultra-short H2-H2O distances and a 1:1 stoichiometry leading to two interpenetrated identical diamond-like sublattices, one comprised of water molecules, the other of hydrogen molecules. At high pressures, nuclear quantum effects involving both hydrogen molecules and the water lattice become dominant, giving rise to a dual-lattice quantum system. In this work, we explore the sequence of pressure- and temperature-driven phase transitions in HH, focusing on the interplay between molecular rotation, orientational ordering, lattice symmetry breaking and hydrogen bond symmetrization. Using a combination of computational modeling based on classical and path-integral molecular dynamics, quantum embedding, and high pressure experiments, including Raman spectroscopy and synchrotron X-ray diffraction at low temperatures and high pressures, we identify signatures of quantum-induced ordering and structural transformations in the C2 phase. Our findings reveal that orientational ordering in HH occurs at much lower pressures than in solid hydrogen, by inducing structural changes in the water network and enhancing the coupling of water and hydrogen dynamics. This work provides new insights into the quantum behavior of hydrogen under extreme mechanochemical confinement and establishes hydrogen-filled ices as a promising platform for the design of hydrogen-rich quantum materials.
In situ time-resolved X-ray absorption spectroscopy of shock-loaded magnesiosiderite
- Dwivedi Anand Prashant
- Hernandez Jean-Alexis
- Balugani Sofia
- Cabaret Delphine
- Cerantola Valerio
- Comboni Davide
- Deldicque Damien
- Guyot François
- Harmand Marion
- Müller Harald
- Sévelin-Radiguet Nicolas
- Snigireva Irina
- Torchio Raffaella
- Vinci Tommaso
- de Rességuier Thibaut
, 2025. Carbonate minerals are important in Earth's system sciences and have been found on Mars and in meteorites and asteroids, highlighting the importance of impacts in planetary processes. While extensively studied under static compression, the behavior of carbonates under shock compression remains underexplored, with no $\textit{in situ}$ X-ray investigations reported so far. Here we investigate natural magnesiosiderite (Fe$_{0.6}$Mg$_{0.4}$CO$_{3}$) under nanosecond laser-driven shock compression at pressures up to 150 GPa, coupled with $\textit{in situ}$ ultrafast synchrotron X-ray absorption spectroscopy (XAS). The interpretation of the experimental spectra is complemented using first-principles absorption cross-section calculations performed on crystalline phases at different pressures and on a dense liquid phase obtained using density functional theory-based molecular dynamics (DFT-MD) simulations. Under laser-driven shock compression, the magnesiosiderite crystal phase remains unchanged up to the melt. Under shock reverberation, the absorption spectra show changes similar to those attributed to a high-spin to low-spin transition observed under static compression. At higher pressures, the laser shock induces the formation of CO$_4$ tetrahedral units in the melt. Upon unloading from the shocked state, only a few nanoseconds later, the original magnesiosiderite phase is recovered. (10.48550/arXiv.2503.00680)
DOI : 10.48550/arXiv.2503.00680
Observation of a mixed close-packed structure in superionic water
- Andriambariarijaona L.
- Stevenson M G
- Bethkenhagen M.
- Lecherbourg L.
- Lefèvre F.
- Vinci T.
- Appel K.
- Baehtz C.
- Benuzzi-Mounaix A.
- Bergermann A.
- Bespalov D.
- Brambrink E.
- Cowan T E
- Cunningham E.
- Descamps A.
- Cafiso S. Di Dio
- Dyer G.
- Fletcher L B
- French M.
- Frost M.
- Galtier E.
- Gleason A E
- Glenzer S H
- Glenn G D
- Guarnelli Y.
- Hartley N J
- He Z.
- Herbert M.-L.
- Hernandez J.-A.
- Heuser B.
- Höppner H.
- Humphries O S
- Husband R.
- Khaghani D.
- Konôpková Z.
- Kuhlke J.
- Garcia A. Laso
- Lee H J
- Lindqvist B.
- Lütgert J.
- Lynn W.
- Masruri M.
- May P.
- Mcbride E E
- Nagler B.
- Nakatsutsumi M.
- Naedler J.-P.
- Ofori-Okai B K
- Pandolfi S.
- Pelka A.
- Preston T R
- Qu C.
- Randolph L.
- Ranjan D.
- Redmer R.
- Rips J.
- Schoenwaelder C.
- Schumacher S.
- Schuster A K
- Schwinkendorf J.-P.
- Strohm C.
- Tang M.
- Toncian T.
- Voigt K.
- Vorberger J.
- Zastrau U.
- Kraus D.
- Ravasio A.
Nature Communications, Nature Publishing Group, 2025, 17, pp.374. The study of superionic (SI) water has been a highly active research area since its theoretical prediction. Despite significant experimental and computational efforts, its melting curve and the stability of different oxygen lattices remain debated, impacting our understanding of SI ice’s peculiar transport properties. Experimental results at lower pressures show disagreement, whereas data at higher pressures are scarce due to the extreme challenges of such experiments. In this work, we present ultrafast X-ray diffraction results of water compressed by multiple shocks to pressures up to ~ 180 GPa. At pressures exceeding 150 GPa and temperatures around 2500 K, our diffraction patterns challenge the pure FCC-SI phase model, providing experimental evidence of the mixed close-packed superionic phase predicted by advanced ab initio calculations. At lower pressures, we observe simultaneous signatures of BCC and FCC structures within a pressure-temperature range consistent with some static-compression experiments, helping to resolve contradictory results in literature. These insights offer new constraints on the stability domains of SI phases and reveal detailed structural features, such as stacking faults. Our results advance the structural understanding of high-pressure SI ice to a level approaching that of ice I polymorphs, with potential implications for waterrich interiors of giant planets. (10.1038/s41467-025-67063-2)
DOI : 10.1038/s41467-025-67063-2
Holographic Gaseous Lenses for High-Power Lasers
- Singh Devdigvijay
- Ou Ke
- Cao Sida
- Perez-Ramirez Victor
- Rajesh Harsha
- Chakraborty Debolina
- Koh Elaine
- Redshaw Caleb
- Dedeler Pelin
- Oudin Albertine
- Wang Michelle
- Mikhailova Julia
- Lancia Livia
- Riconda Caterina
- Michel Pierre
- Edwards Matthew
, 2025. The capabilities of the world's highest energy and peak-power pulsed lasers are limited by optical damage, and further advances in high-intensity laser science will require optics that are substantially more robust than existing components. We describe here the experimental demonstration of off-axis diffractive gaseous lenses capable of withstanding extreme laser fluence and immune to cumulative damage. We used less than 8 mJ of energy from interfering ultraviolet laser pulses to holographically write millimeter-scale diffractive gas lenses into an ozone, oxygen, and carbon-dioxide gas mixture. These lenses allowed us to focus, defocus, and collimate 532-nm, 210-mJ nanosecond laser pulses at fluences up to 35 J/cm$^2$ and 800-nm, 35-fs, 28-mJ femtosecond pulses at intensities up to 55 TW/cm$^2$, achieving greater than 80% diffraction efficiency. We also show that that beam pointing, divergence, and diffraction efficiency are stable while operating at 10 Hz. These diffractive lenses are simple holograms, and the principles demonstrated here extended to other types of optics suggests that gaseous optics could enable arbitrary, damage-resistant manipulation of intense light for next-generation ultra-high-power lasers. (10.48550/arXiv.2510.02659)
DOI : 10.48550/arXiv.2510.02659
Simultaneous hard x-ray Talbot phase and dark-field imaging in laser experiments at XFEL facilities
- Bouffetier V.
- Valdivia M.
- Ceurvorst L.
- Stutman D.
- Rigon G.
- Albertazzi Bruno
- Koenig M.
- Pikuz T.
- Ozaki N.
- Nakamura H.
- Hironaka Y.
- Miyanishi K.
- Yabuuchi T.
- Togashi T.
- Sueda K.
- Yabashi M.
- Goudal T.
- Mancelli D.
- Casner A.
- Pérez-Callejo G.
Review of Scientific Instruments, American Institute of Physics, 2025, 96 (12), pp.123508. X-ray Free Electron Laser (XFEL) facilities offer unprecedented opportunities to advance instrumentation for studying matter under extreme conditions. In this study, we harnessed the enhanced x-ray capabilities of XFELs to demonstrate dark field imaging in laser-driven experiments at XFEL facilities. Utilizing a Talbot x-ray interferometer, we simultaneously captured transmission, dark-field, and differential phase contrast radiographs of laser-driven metallic foils. Our work showcases the feasibility of single-shot grating-based Talbot x-ray dark-field imaging in pump-probe experiments at XFEL facilities, opening doors to a wide range of hard x-ray imaging applications in material science and high-energy density physics. (10.1063/5.0307618)
DOI : 10.1063/5.0307618
Strong-field ionization in particle-in-cell simulations
- Mironov A.A
- Gelfer E.G
- Tupitsyn I.I
- Beck A
- Jirka M
- Klimo O
- Meuren S
- Oberreit G
- Smorodnikova T
- Taïeb R
- Weber S
- Riconda C
- Grech M
- Popruzhenko S.V
Physical Review E, American Physical Society (APS), 2025, 112 (5), pp.055202. The inclusion of the process of multiple ionization of atoms in high-intensity electromagnetic fields into particle-in-cell (PIC) codes applied to the simulation of laser-plasma interactions is a challenging task. In this paper, we first revisit ionization rates as given by the Smirnov-Chibisov and Perelomov-Popov-Terent'yev formulas within the paradigm of sequential tunnel ionization. We analyze the limit of validity and possible inconsistencies of this approach. We show that a strongly limiting factor to a precise description of ionization is the competing contribution of different sequential ionization processes. To solve this an algorithm is proposed that allows one to find the dominant nonsequential path of tunnel ionization and significantly improves the precision in simulations. This procedure is implemented in the PIC code SMILEI, and includes the dependence of the ionization rates on the magnetic quantum number of the level. The sensitivity to variations in the ionization model is studied via full simulations of the ionization of an argon target by an incident high-intensity laser pulse. Finally, we analyze generalizations of the Perelomov-Popov-Terent'yev rate developed to describe the barrier suppression ionization in high fields and discuss the necessity and possibility of including these extensions in PIC simulations. (10.1103/zlzb-kqtw)
DOI : 10.1103/zlzb-kqtw
X-ray thermal diffuse scattering as a texture-robust temperature diagnostic for dynamically compressed solids
- Heighway P G
- Peake D J
- Stevens T
- Wark J S
- Albertazzi B
- Ali S J
- Antonelli L
- Armstrong M R
- Baehtz C
- Ball O B
- Banerjee S
- Belonoshko A B
- Bolme C A
- Bouffetier V
- Briggs R
- Butcher T
- Di S
- Cafiso Dio
- Cerantola V
- Chantel J
- Di Cicco
- Coleman A L
- Collier J
- Collins G
- Comley A J
- Coppari F
- Cowan T E
- Cristoforetti G
- Cynn H
- Descamps A
- Dorchies F.
- Duff M J
- Dwivedi A
- Edwards C
- Eggert J H
- Errandonea D
- Fiquet G
- Galtier E
- Laso A
- Ginestet H
- Gizzi L
- Gleason S
- Goede J M
- Gonzalez M G
- Gorman M G
- Hernandez-Gomez A
- Higginbotham H
- Höppner O S
- Humphries R J
- Husband T M
- Hwang D A
- Keen J
- Kim P
- Koester Z
- Konopkova D
- Krygier L
- Labate A E
- Lazicki Y
- Lee H.-P
- Liermann P
- Massani E E
- Mcbride C
- Mcguire J D
- Mchardy D
- Mcgonegle R S
- Mcwilliams S
- Merkel G
- Morard B
- Nagler M
- Nguyen-Cong A.-M
- Norton I I
- Oleynik C
- Otzen N
- Ozaki S
- Pandolfi A
- Pelka K A
- Pereira J P
- Prescher T
- Preston L
- Randolph D
- Ranjan A
- Ravasio J
- Rips D
- Santamaria-Perez D J
- Savage M
- Schoelmerich J.-P
- Schwinkendorf S
- Singh J
- Smith R F
- Smith A
- Sollier J
- Spear C
- Spindloe M
- Stevenson C
- Strohm T.-A
- Suer M
- Toncian T
- Buakor K
- Cicco A Di
- Laso Garcia A
- Gleason A
- Goede S
- Gonzalez J M
- Harmand M
- Hartley N J
- Hernandez-Gomez C
- Higginbotham A
- Höppner H
- Humphries O S
- Husband R J
- Hutchinson T M
- Hwang H
- Keen D A
- Kim J
- Koester P
- Konopkova Z
- Kraus D
- Krygier A
- Labate L
- Lazicki A E
- Lee Y
- Liermann H.-P
- Mason P
- Masruri M
- Massani B
- Mcbride E E
- Mcguire C
- Mchardy J D
- Mcgonegle D
- Mcwilliams R S
- Merkel S
- Morard G
- Nagler B
- Nakatsutsumi M
- Nguyen-Cong K
- Norton A.-M
- Oleynik I I
- Otzen C
- Ozaki N
- Pandolfi S
- Pelka A
- Pereira K A
- Phillips J P
- Prescher C
- Preston T
- Randolph L
- Ranjan D
- Ravasio A
- Rips J
- Mcmahon M I
- Savage D J
- Schoelmerich M
- Schwinkendorf J.-P
- Singh S
- Smith J
- Sollier A
- Spear J
- Spindloe C
- Stevenson M
- Strohm C
- Suer T.-A
- Tang M
- Toncian M
- Tracy S J
- Trapananti A
- Tschentscher T
- Tyldesley M
- Vennari C E
- Vinci T
- Vogel S C
- Volz T J
- Vorberger J
- Willman J T
- Wollenweber L
- Zastrau U
- Brambrink E
- Appel K
Journal of Applied Physics, American Institute of Physics, 2025, 138, pp.155903. We present a model of x-ray thermal diffuse scattering (TDS) from a cubic polycrystal with an arbitrary crystallographic texture, based on the classic approach of Warren [B. E. Warren, Acta Crystallogr. 6, 803 (1953)]. We compare the predictions of our model with femtosecond x-ray diffraction patterns gathered from ambient and dynamically compressed rolled copper foils obtained at the High Energy Density instrument of the European X-Ray Free-Electron Laser facility and find that the texture-aware TDS model yields more accurate results than does the conventional powder model owed to Warren. Nevertheless, we further show: with sufficient angular detector coverage, the TDS signal is largely unchanged by sample orientation and in all cases strongly resembles the signal from a perfectly random powder; shot-to-shot fluctuations in the TDS signal resulting from grain-sampling statistics are at the percent level, in stark contrast to the fluctuations in the Bragg-peak intensities (which are over an order of magnitude greater); and TDS is largely unchanged even following texture evolution caused by compression-induced plastic deformation. We conclude that TDS is robust against texture variation, making it a flexible temperature diagnostic applicable just as well to off-the-shelf commercial foils as to ideal powders. (10.1063/5.0295250)
DOI : 10.1063/5.0295250
Coherent beam combining strategies for highenergy and high-repetition rate lasers dedicated to inertial nuclear fusion applications
- Lebegue Pierre
- Froidevaux Marie
- Ohland Jonas Benjamin
- Rapeneau Cyril
- Badarau Doina
- de Sousa Joanna
- Meignien Loïc
- Doudet Ivan
- Chan Nolan
- Wattellier Benoit
- Audebert Patrick
- Papadopoulos Dimitris
- Druon Frédéric
Optics Express, Optical Society of America - OSA Publishing, 2025, 33 (22), pp.45615. Spatial Coherent Beam Combining (CBC) strategies are particularly promising for lasers dedicated to nuclear fusion applications in the purpose of developing high-energy and high-repetition-rate lasers. Let us examine their potential application to high-energy, largesize beams with repetition rates that preclude phase correlation between subsequent pulses. Both passive and active CBC approaches are investigated in this study to identify the most appropriate and effective strategy for large-aperture, high-energy laser amplifiers. Specific experiments have been conducted to validate promising architectures for lasers dedicated to inertial confinement fusion (ICF) applications. Based on these experimental results, examples of suitable and well-adapted setups are proposed (10.1364/OE.574715)
DOI : 10.1364/OE.574715
Tailoring coherent beam combined fiber laser pulse trains for laser-matter interaction applications
- Lechevalier Corentin
- Fsaifes Ihsan
- Andrieu Jordan
- Ranély-Vergé-Dépré Claude-Alban
- Jovanovic Igor
- Chanteloup Jean-Christophe
, 2025, pp.ATu1A. 5. <div><p>We report on a versatile coherently combined ultrashort fiber laser allowing an independent peak and average power adjustment, pulse-on-demand, and repetition rate management, needed for laser-matter interaction applications.</p></div> (10.1364/ASSL.2025.ATu1A.5)
DOI : 10.1364/ASSL.2025.ATu1A.5
Ultrafast filamentation in air at 333 kHz employing coherently combined fiber laser
- Fsaifes Ihsan
- Lechevalier Corentin
- Andrieu Jordan
- Frigerio Leandro
- Burger Milos
- Jovanovic Igor
- Chanteloup Jean-Christophe
, 2025, pp.JW2A.4. <div><p>Plasma filaments in the air are generated using a coherently combined ultrashort fiber laser, reaching the highest repetition rate of 333 kHz reported to date. Cumulative effects of pulse burst on the filament length and longitudinal shift are investigated.</p></div> (10.1364/ASSL.2025.JW2A.4)
DOI : 10.1364/ASSL.2025.JW2A.4
Indirectly LED-pumped Nd:glass regenerative amplifier
- Nourry-Martin Maxime
- Thellier Elio
- Le Blanc Catherine
- Meignien Loïc
- Audebert Patrick
- Druon Frederic
- Georges Patrick
- Balembois Francois
Optics Express, Optical Society of America - OSA Publishing, 2025. We demonstrate the first LED-pumped Nd:glass regenerative amplifier. It delivers 2 ns pulses at 1053 nm with an energy of 3.8 mJ at a repetition rate of 2 Hz. This performance is achieved using a Ce:LuAG luminescent concentrator producing 3.4 kW of optical peak power in the yellow spectral range and pumped by 3200 blue LEDs. This indirect LED pumped technology demonstrates high power-scaling capabilities and shows great potential for high energy Nd:glass laser chains. (10.1364/OE.575169)
DOI : 10.1364/OE.575169
Efficient ion re-acceleration in laboratory-produced interpenetrating collisionless shocks
- Yao W
- Cohen I
- Gerona P. Suarez
- Ahmed H
- Bott A.F.A
- Chen S.N
- Cook M
- Lelievre Ronan
- Martin P
- Waltenspiel Tessa
- Antici P
- Béard Jérome
- Borghesi M
- Caprioli D
- Ciardi A
- d'Humières Emmanuel
- François M
- Gremillet Laurent
- Marcowith Alexandre
- Miceli M
- Seebaruth T
- Orlando S
- Fuchs J
, 2025. Although the origin of cosmic rays (CRs) remains an open question, collisionless magnetized shock waves are widely regarded as key sites for particle acceleration. Recent theories further suggest that shock-shock collisions in stellar clusters could provide the additional acceleration needed to explain the observed high-energy CR spectrum. Here, we investigate this hypothesis through a laser-based experiment that creates magnetized plasma conditions similar to astrophysical environments. Our results demonstrate that interpenetrating collisionless shocks can significantly boost the energy of ambient protons previously energized by the individual shocks, while also improving the overall acceleration efficiency. Numerical kinetic simulations corroborate these findings, revealing that protons are reaccelerated via their bouncing motion in the convective electric fields of the colliding magnetized flows. By allowing to highly energize ambient protons, our novel colliding-shock platform opens the prospect to test the long-discussed mechanism of diffusive shock acceleration in a controlled laboratory setting.
Experimental evidence of stimulated Raman rescattering in laser-plasma interaction
- Marquès J. -R.
- Pérez F.
- Loiseau P.
- Lancia L.
- Briand C.
- Depierreux S.
- Grech M.
- Riconda C.
Physical Review Letters, American Physical Society, 2025, 135 (10), pp.105101. We present the first experimental evidence of stimulated Raman re-scattering of a laser in plasma: The scattered light produced by the Raman instability is intense enough to scatter again through the same instability. Although never observed, re-scattering processes have been studied theoretically and numerically for many years in the context of inertial confinement fusion (ICF), since the plasma waves they generate could bootstrap thermal electrons to high energies [Phys. Rev. Lett. \textbf{110}, 165001 (2013)], preheating the fuel and degrading ignition conditions. Our experimental results are obtained with a spatially smoothed laser beam consisting of many speckles, with an average intensity around $10^{14}$ W/cm$^2$ and close to $10^{15}$ W/cm$^2$ in the speckles, such as those usually used in direct-drive ICF. Kinetic and hydrodynamic simulations show good agreement with the observations. (10.1103/r7th-rq38)
DOI : 10.1103/r7th-rq38
Testing strong-field QED with the avalanche precursor
- Mironov A.A
- Bulanov S.S
- Di Piazza A
- Grech M
- Lancia L
- Meuren S
- Palastro J
- Riconda C
- Rinderknecht H.G
- Tzeferacos P
- Gregori G
Physics of Plasmas, American Institute of Physics, 2025, 32 (9), pp.093302. A two-beam high-power laser facility is essential for the study of one of the most captivating phenomena predicted by strong-field quantum electrodynamics (QED) and yet unobserved experimentally: the avalanche-type cascade. In such a cascade, the energy of intense laser light can be efficiently transformed into high-energy radiation and electron-positron pairs. The future 50-petawatt-scale laser facility NSF OPAL will provide unique opportunities for studying such strong-field QED effects, as it is designed to deliver two ultra-intense, tightly focused laser pulses onto the interaction point. In this work, we investigate the potential of such a facility for studying elementary particle and plasma dynamics deeply in the quantum radiation-dominated regime, and the generation of QED avalanches. With 3D particle-in-cell simulations, we demonstrate that QED avalanche precursors can be reliably triggered under realistic laser parameters and layout (namely, focusing $f/2$, tilted optical axes, and non-ideal co-pointing) with the anticipated capabilities of NSF OPAL. We demonstrate that seed electrons can be efficiently injected into the laser focus by using targets of three types: a gas of heavy atoms, an overcritical plasma, and a thin foil. A strong positron and high-energy photon signal is generated in all cases. The cascade properties can be identified from the final particle distributions, which have a clear directional pattern. At increasing laser field intensity, such distributions provide signatures of the transition, first, to the radiation-dominated interaction regime, and then to a QED avalanche. Our findings can also be used for designing related future experiments. (10.1063/5.0283438)
DOI : 10.1063/5.0283438
Plasma dynamics of an Al plasma in AlTi or AlAu mixtures heated by the PICO2000 ultra-intense laser pulse
- Lecherbourg L.
- Baton S.
- Blancard Ch.
- Chaleil A.
- Cossé P.
- Duthoit L.
- Faussurier G.
- Gremillet L.
- Loupias B.
- Pain J.-Ch.
- Pérez F.
- Poujade O.
- Reverdin C.
- Renaudin P.
Physics of Plasmas, American Institute of Physics, 2025, 32 (9). The rapid cooling dynamics of thin solid foils heated by an ultra-intense (∼1018 Wcm−2) picosecond laser pulse are experimentally studied using three independent diagnostics based on a time-integrated and time-resolved x-ray emission spectroscopy as well as 2D x-ray imaging. Targets consist of plastic foils with buried Al, Al42Ti58, or Al85Au15 layers, where Al emission lines are used to infer the plasma conditions. Our measurements indicate that the Al K-shell emission occurs over a shorter duration and from a narrower region in AlTi or AlAu mixtures compared to pure Al samples, and that the average temperature is lower when increasing the atomic number of the high-Z element in the mixture. The TROLL radiation hydrodynamics code, coupled with the SAPHyR collisional radiative model, is used to infer the plasma heating conditions. This numerical platform has been able to consistently simulate the experimental results from the three diagnostics, allowing us to bypass the use of expensive PIC simulations. 2D simulations clearly show the importance of taking into account the particular 2D shape of the energy deposition, according to the measured radial laser intensity profile. The satisfactory agreement between simulations and measurements suggests that, for the relatively long laser pulse considered (∼1.3 ps), the target bulk is primarily heated through direct collisions with fast electrons. Furthermore, simulations indicate that significant radiative cooling is observed in AlAu targets. (10.1063/5.0272025)
DOI : 10.1063/5.0272025
Evidence for ultra-water-rich ammonia hydrates stabilized in icy exoplanetary mantles
- Mondal Anshuman
- Mohrbach Katharina
- Fedotenko Timofey
- Bethkenhagen Mandy
- Liermann Hanns-Peter
- Sanchez-Valle Carmen
, 2025. Understanding the behavior of the water-ammonia system at high pressure-high temperature conditions is important for modeling the internal dynamics of exoplanet icy mantles. Conventionally, mixtures of ammonia hemihydrate AHH (2:1 ammonia-water molar ratio) and H2O ice VII have been regarded as the ultimate solid phase assembly in the system. Here we report evidence for chemical reactions between AHH and ice VII above 750 K and 16 GPa that stabilize water-rich ammonia hydrates, including a novel ultra-water rich hydrate NH3.6H2O (1:6 ratio) coexisting with ammonia dihydrate ADH (1:2 ratio) and excess ice VII. This assembly is stable up to at least 30 GPa and 1600 K and can be quenched to room temperature. Our results demonstrate that water-rich ammonia hydrates are favored in the icy mantle of 1-2 MEarth exoplanets regardless of the ammonia content of the hydrate crystallized during accretion and/or evolution as long as excess H2O ice is available. The buoyancy contrast between water-rich hydrates and ice VII may lead to chemical stratification in exoplanet icy mantles, hence affecting their thermal evolution.
Laser-driven proton sources for efficient radiation testing
- D’orsi Beatrice
- Altomare Corrado
- Ampollini Alessandro
- Astorino Maria Denise
- Bazzano Giulia
- Catrix Elias
- Cemmi Alessia
- Colangeli Andrea
- Di Sarcina Ilaria
- Lazzaro Daniele Salvatore
- Lelievre Ronan
- Loreti Stefano
- Fourmaux Sylvain
- Fuchs Julien
- Nenzi Paolo
- Pagano Guglielmo
- Panza Fabio
- Ronsivalle Concetta
- Scifo Jessica
- Vallières Simon
- Antici Patrizio
Scientific Reports, Nature Publishing Group, 2025, 15, pp.27181. Several fields such as particle physics, space exploration, and high-energy physics, use Commercial Off-The-Shelf (COTS) electronic components in a high-radiation operative environment. These operating conditions can cause significant damage to electronic circuits, affecting their operational features and thus the reliability of the entire facility. Qualifying and characterizing these components against radiation is essential to ensure their proper functioning in harsh conditions. This study investigates the effect of stress-testing electronic components used in high-radiation environments with various types of radiation sources. The components were exposed to gamma rays, laser-driven protons, conventionally accelerated protons, and neutrons, analyzing the devices parameters after different irradiation conditions. The results indicate significant degradation in electrical performance due to radiation-induced defects and significant variations of the effects at same dose delivery. We show that laser-driven proton irradiation achieves equivalent stress-testing with doses two orders of magnitude lower and much quicker than other radiation sources, demonstrating a much higher stress-testing efficiency. (10.1038/s41598-025-05682-x)
DOI : 10.1038/s41598-025-05682-x
Zeeman splitting observations in laser-produced magnetized blast waves
- Triantafyllidis A.
- Marquès J.-R.
- Ferri S.
- Calisti A.
- Benkadoum Y.
- de León Y.
- Dearling A.
- Ciardi A.
- Béard J.
- Lagarrigue J.-M.
- Ozaki N.
- Koenig M.
- Albertazzi Bruno
Matter and Radiation at Extremes, AIP Publishing, 2025, 10 (4). We report the observation of Zeeman splitting in multiple spectral lines emitted by a laser-produced, magnetized plasma (1–3 × 1018 cm−3, 1–15 eV) in the context of a laboratory astrophysics experiment under a controlled magnetic field up to 20 T. Nitrogen lines (NII) in the visible range (563–574 nm) were used to diagnose the magnetic field and plasma conditions. This was performed by coupling our data with the Stark–Zeeman line-shape code PPPB. The excellent agreement between experiment and simulations paves the way for a non-intrusive experimental platform to get time-resolved measurements of the local magnetic field in laboratory plasmas. (10.1063/5.0256859)
DOI : 10.1063/5.0256859
PIAFS: A 2D nonlinear hydrodynamics code to model gaseous optics
- Oudin A.
- Ghosh D.
- Riconda C.
- Lancia L.
- Kur E.
- Ou K.
- Perez-Ramirez V M
- Lee J.
- Edwards M R
- Michel P.
Physics of Plasmas, American Institute of Physics, 2025, 32 (7), pp.072714. The survivability of final optics is expected to be a major challenge for all future inertial fusion energy concepts. Due to their higher damage threshold, gaseous optics have been identified as a promising solution to this problem. Gaseous optics can be created through the photo-absorption of spatially-modulated UV light , which induces various chemical processes that heat the gas. This heating leads to a pressure perturbation, which in turn launches a density perturbation that can imprint a refractive index modulation such as a grating. In this article, we introduce a parallel C/C++ code to simulate gaseous optics. PIAFS2D is a high-order conservative finite-difference code to solve the compressible Navier-Stokes equations along with the photochemical heating sources on Cartesian grids. The simulations are validated by the linear theory derived in a previous paper [P. Michel et al., Phys. Rev. Applied 22, 024014 (2024)]. For larger perturbations, the behavior of the systemparticularly the evolution of the generated acoustic wave-demonstrates strong nonlinearity. PIAFS2D allows the study of nonlinear behaviors, and can be used for the design of high-efficiency gaseous optics elements in realistic experimental conditions. (10.1063/5.0268318)
DOI : 10.1063/5.0268318
Radiation-induced photoluminescent colour centres in lithium fluoride films for the detection of monochromatic hard X-rays
- Vincenti M.A.
- Montereali R.M.
- Nichelatti E.
- Nigro V.
- Piccinini M.
- Koenig M.
- Mabey P.
- Rigon G.
- Dabrowski H.J.
- Benkadoum Y.
- Mercere P.
- da Silva P.
- Ozaki N.
- Filippov E.D.
- Pikuz S.
- Pikuz T.
- Albertazzi Bruno
- Makarov S.
Journal of Instrumentation, IOP Publishing, 2025, 20 (07), pp.C07001. <div><p>Optically-transparent LiF film radiation imaging detectors of three different thicknesses, grown by thermal evaporation on Si(100) substrates and irradiated with monochromatic 7 keV X-rays at several doses in the range between 13 and 4.5×10 3 Gy, were investigated by fluorescence microscopy to evaluate their visible photoluminescence response of X-ray induced colour centres and their spatial resolution. By edge-enhancement imaging experiments, performed by irradiating LiF film detectors with an Au mesh in front of them, a spatial resolution of ∼0.3 μm was estimated. This high spatial resolution, combined with the large field of view and the wide dynamic range offered by LiF detectors, encourages their use in X-ray imaging and for high-energy density experiments in synchrotron facilities.</p></div> (10.1088/1748-0221/20/07/C07001)
DOI : 10.1088/1748-0221/20/07/C07001
Calibration and characterization of the line-VISAR diagnostic at the HED-HIBEF instrument at the European XFEL
- Descamps A.
- Hutchinson T M
- Briggs R.
- Mcbride E E
- Millot M.
- Michelat T.
- Eggert J H
- Albertazzi B.
- Antonelli L.
- Armstrong M R
- Baehtz C.
- Ball O B
- Banerjee S.
- Belonoshko A B
- Benuzzi-Mounaix A.
- Bolme C A
- Bouffetier V.
- Buakor K.
- Butcher T.
- Cerantola V.
- Chantel J.
- Coleman A L
- Collier J.
- Collins G.
- Comley A J
- Coppari F.
- Cowan T E
- Crépisson C.
- Cristoforetti G.
- Cynn H.
- Di Dio Cafiso S.
- Dorchies F.
- Duff M J
- Dwivedi A.
- Errandonea D.
- Galtier E.
- Ginestet Helene
- Gizzi L.
- Gleason A.
- Goede S.
- Gonzalez J M
- Gorman M G
- Harmand M.
- Hartley N J
- Heighway P G
- Hernandez-Gomez C.
- Higginbotham A.
- Höppner H.
- Husband R J
- Hwang H.
- Kim J.
- Koester P.
- Konopkova Z.
- Kraus D.
- Krygier A.
- Labate L.
- Garcia A. Laso
- Lazicki A E
- Lee Y.
- Mason P.
- Masruri M.
- Massani B.
- Mcgonegle D.
- Mcguire C.
- Mchardy J D
- Mcwilliams R S
- Merkel S.
- Morard G.
- Nagler B.
- Nakatsutsumi M.
- Nguyen-Cong K.
- Norton A.-M.
- Oleynik I I
- Otzen C.
- Ozaki N.
- Pandolfi S.
- Peake D J
- Pelka A.
- Pereira K A
- Phillips J P
- Prescher C.
- Preston T R
- Randolph L.
- Ranjan D.
- Ravasio A.
- Redmer R.
- Rips J.
- Santamaria-Perez D.
- Savage D J
- Schoelmerich M.
- Schwinkendorf J-P.
- Singh S.
- Smith J.
- Smith R F
- Sollier A.
- Spear J.
- Spindloe C.
- Stevenson M.
- Strohm C.
- Suer T-A.
- Tang M.
- Tschentscher T.
- Toncian M.
- Toncian T.
- Tracy S J
- Tyldesley M.
- Vennari C E
- Vinci T.
- Volz T J
- Vorberger J.
- Walsh J P S
- Wark J S
- Willman J T
- Wollenweber L.
- Zastrau U.
- Brambrink E.
- Appel K.
- Mcmahon M I
Review of Scientific Instruments, American Institute of Physics, 2025, 96 (7), pp.075206. In dynamic-compression experiments, the line-imaging Velocity Interferometer System for Any Reflector (VISAR) is a well-established diagnostic used to probe the velocity history, including wave profiles derived from dynamically compressed interfaces and wavefronts, depending on material optical properties. Knowledge of the velocity history allows for the determination of the pressure achieved during compression. Such a VISAR analysis is often based on Fourier transform techniques and assumes that the recorded interferograms are free from image distortions. In this paper, we describe the VISAR diagnostic installed at the HED-HIBEF instrument located at the European XFEL along with its calibration and characterization. It comprises a two-color (532, 1064 nm), three-arm (with three velocity sensitivities) line imaging system. We provide a procedure to correct VISAR images for geometric distortions and evaluate the performance of the system using Fourier analysis. We finally discuss the spatial and temporal calibrations of the diagnostic. As an example, we compare the pressure extracted from the VISAR analysis of shock-compressed polyimide and silicon. (10.1063/5.0271027)
DOI : 10.1063/5.0271027

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