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Dornheim T, Döppner T, Baczewski AD, Tolias P, Böhme MP, Moldabekov ZA, Gawne T, Ranjan D, Chapman DA, MacDonald MJ, Preston TR, Kraus D, Vorberger J. X-ray Thomson scattering absolute intensity from the f-sum rule in the imaginary-time domain. Sci Rep 2024; 14:14377. [PMID: 38909077 PMCID: PMC11193768 DOI: 10.1038/s41598-024-64182-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 06/05/2024] [Indexed: 06/24/2024] Open
Abstract
We present a formally exact and simulation-free approach for the normalization of X-ray Thomson scattering (XRTS) spectra based on the f-sum rule of the imaginary-time correlation function (ITCF). Our method works for any degree of collectivity, over a broad range of temperatures, and is applicable even in nonequilibrium situations. In addition to giving us model-free access to electronic correlations, this new approach opens up the intriguing possibility to extract a plethora of physical properties from the ITCF based on XRTS experiments.
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Affiliation(s)
- T Dornheim
- Center for Advanced Systems Understanding (CASUS), 02826, Görlitz, Germany.
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany.
| | - T Döppner
- Lawrence Livermore National Laboratory (LLNL), California, 94550, Livermore, USA
| | - A D Baczewski
- Center for Computing Research, Sandia National Laboratories, Albuquerque, NM, 87185, USA
| | - P Tolias
- Space and Plasma Physics, Royal Institute of Technology (KTH), Stockholm, 100 44, Sweden
| | - M P Böhme
- Center for Advanced Systems Understanding (CASUS), 02826, Görlitz, Germany
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
- Technische Universität Dresden, 01062, Dresden, Germany
| | - Zh A Moldabekov
- Center for Advanced Systems Understanding (CASUS), 02826, Görlitz, Germany
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
| | - Th Gawne
- Center for Advanced Systems Understanding (CASUS), 02826, Görlitz, Germany
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
| | - D Ranjan
- Institut für Physik, Universität Rostock, 18057, Rostock, Germany
| | - D A Chapman
- First Light Fusion, Yarnton, Oxfordshire, UK
| | - M J MacDonald
- Lawrence Livermore National Laboratory (LLNL), California, 94550, Livermore, USA
| | | | - D Kraus
- Institut für Physik, Universität Rostock, 18057, Rostock, Germany
| | - J Vorberger
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
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Engel RY, Alexander O, Atak K, Bovensiepen U, Buck J, Carley R, Cascella M, Chardonnet V, Chiuzbaian GS, David C, Döring F, Eschenlohr A, Gerasimova N, de Groot F, Guyader LL, Humphries OS, Izquierdo M, Jal E, Kubec A, Laarmann T, Lambert CH, Lüning J, Marangos JP, Mercadier L, Mercurio G, Miedema PS, Ollefs K, Pfau B, Rösner B, Rossnagel K, Rothenbach N, Scherz A, Schlappa J, Scholz M, Schunck JO, Setoodehnia K, Stamm C, Techert S, Vinko SM, Wende H, Yaroslavtsev AA, Yin Z, Beye M. Electron population dynamics in resonant non-linear x-ray absorption in nickel at a free-electron laser. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2023; 10:054501. [PMID: 37841290 PMCID: PMC10576398 DOI: 10.1063/4.0000206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 09/20/2023] [Indexed: 10/17/2023]
Abstract
Free-electron lasers provide bright, ultrashort, and monochromatic x-ray pulses, enabling novel spectroscopic measurements not only with femtosecond temporal resolution: The high fluence of their x-ray pulses can also easily enter the regime of the non-linear x-ray-matter interaction. Entering this regime necessitates a rigorous analysis and reliable prediction of the relevant non-linear processes for future experiment designs. Here, we show non-linear changes in the L 3 -edge absorption of metallic nickel thin films, measured with fluences up to 60 J/cm2. We present a simple but predictive rate model that quantitatively describes spectral changes based on the evolution of electronic populations within the pulse duration. Despite its simplicity, the model reaches good agreement with experimental results over more than three orders of magnitude in fluence, while providing a straightforward understanding of the interplay of physical processes driving the non-linear changes. Our findings provide important insights for the design and evaluation of future high-fluence free-electron laser experiments and contribute to the understanding of non-linear electron dynamics in x-ray absorption processes in solids at the femtosecond timescale.
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Affiliation(s)
| | - Oliver Alexander
- Department of Physics, Imperial College London, London, United Kingdom
| | - Kaan Atak
- Deutsches Elektronen-Synchrotron DESY, Germany
| | | | | | | | | | - Valentin Chardonnet
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement LCPMR, Paris, France
| | - Gheorghe Sorin Chiuzbaian
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement LCPMR, Paris, France
| | | | | | - Andrea Eschenlohr
- Faculty of Physics and Center for Nanointegration Duisburg-Essen CENIDE, University of Duisburg-Essen, Duisburg, Germany
| | | | - Frank de Groot
- Debye Institute for Nanomaterials Science, Inorganic Chemistry and Catalysis, Utrecht University, Utrecht, The Netherlands
| | | | | | | | - Emmanuelle Jal
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement LCPMR, Paris, France
| | - Adam Kubec
- Paul Scherrer Institut, Villigen, Switzerland
| | | | | | - Jan Lüning
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany
| | | | | | | | | | - Katharina Ollefs
- Faculty of Physics and Center for Nanointegration Duisburg-Essen CENIDE, University of Duisburg-Essen, Duisburg, Germany
| | - Bastian Pfau
- Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Berlin, Germany
| | | | | | - Nico Rothenbach
- Faculty of Physics and Center for Nanointegration Duisburg-Essen CENIDE, University of Duisburg-Essen, Duisburg, Germany
| | | | | | | | | | | | | | | | | | - Heiko Wende
- Faculty of Physics and Center for Nanointegration Duisburg-Essen CENIDE, University of Duisburg-Essen, Duisburg, Germany
| | | | | | - Martin Beye
- Author to whom correspondence should be addressed:
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Chen ZB. On the development of relativistic distorted wave approximation for the energies and collision dynamics of atoms or ions subjected to the outside plasma. PHYSICS OF PLASMAS 2022; 29. [DOI: 10.1063/5.0115626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
In this manuscript, we present the development of a relativistic distorted wave method for determining the energies and collision dynamics of plasma-immersed atoms or ions. The methodology is based on the Dirac–Coulomb Hamiltonian, in which contributions from relativity and higher order effects, such as quantum electrodynamics and Breit interaction, are incorporated. The key element in this method is that a modified Debye–Hückel approximation is employed to represent the effect of plasma screening. In order to correctly describe the (bound and continuous state) wave functions, a self-consistent field calculation incorporating the shielding potential is performed within the fully relativistic framework. The particle interaction within the scattering matrix element of the excitation process is described by the shielded Coulomb interaction. The present technique is illustrated by calculations of energy, line shift, transition probability, electron-impact excitation/ionization cross section, and photoionization cross section of a few-electron system confined in plasma environments. The present model is tested and validated against a number of known cases (simulations are made for the He-like Al11+ ion) in the literatures. Numerical results demonstrate that the modifications to the Coulomb potential proposed in the spatial and temporal criteria of the Debye–Hückel approximation allow us to improve the theoretical description of the plasma shielding and thus the dynamical processes in dense plasmas. Comparisons of our computational predictions and the recent experimental measurements are performed. The current work not only has far-reaching implications for our understanding of the dense plasma screening, but also has potential applications in fusion, laboratory astrophysics, and related disciplines.
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Affiliation(s)
- Zhan-Bin Chen
- School of Science, Hunan University of Technology , Zhuzhou 412007, People's Republic of China
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