Electron Dynamics at High-Energy Densities in Nickel from Non-linear Resonant X-ray Absorption Spectra

Robin Y. Engel; Oliver Alexander; Kaan Atak; Uwe Bovensiepen; Jens Buck; Robert Carley; Michele Cascella; Valentin Chardonnet; Gheorghe Sorin Chiuzbaian; Christian David; Florian Döring; Andrea Eschenlohr; Natalia Gerasimova; Frank de Groot; Loïc Le Guyader; Oliver S. Humphries; Manuel Izquierdo; Emmanuelle Jal; Adam Kubec; Tim Laarmann; Charles-Henri Lambert; Jan Lüning; Jonathan P. Marangos; Laurent Mercadier; Giuseppe Mercurio; Piter S. Miedema; Katharina Ollefs; Bastian Pfau; Benedikt Rösner; Kai Rossnagel; Nico Rothenbach; Andreas Scherz; Justine Schlappa; Markus Scholz; Jan O. Schunck; Kiana Setoodehnia; Christian Stamm; Simone Techert; Sam M. Vinko; Heiko Wende; Alexander A. Yaroslavtsev; Zhong Yin; Martin Beye

doi:10.1063/4.0000206

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arXiv · 2211.17008

Electron Dynamics at High-Energy Densities in Nickel from Non-linear Resonant X-ray Absorption Spectra

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Abstract

The pulse intensity from X-ray free-electron lasers (FELs) can create extreme excitation densities in solids, entering the regime of non-linear X-ray-matter interactions. We show L3-edge absorption spectra of metallic nickel thin films with fluences entering a regime where several X-ray photons are incident per absorption cross-section. Main features of the observed non-linear spectral changes are described with a predictive rate model for electron population dynamics during the pulse, utilizing a fixed density of states and tabulated ground-state properties.

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Robin Y. Engel, Oliver Alexander, Kaan Atak, Uwe Bovensiepen, Jens Buck, Robert Carley, Michele Cascella, Valentin Chardonnet, Gheorghe Sorin Chiuzbaian, Christian David, Florian Döring, Andrea Eschenlohr, Natalia Gerasimova, Frank de Groot, Loïc Le Guyader, Oliver S. Humphries, Manuel Izquierdo, Emmanuelle Jal, Adam Kubec, Tim Laarmann, Charles-Henri Lambert, Jan Lüning, Jonathan P. Marangos, Laurent Mercadier, Giuseppe Mercurio, Piter S. Miedema, Katharina Ollefs, Bastian Pfau, Benedikt Rösner, Kai Rossnagel, Nico Rothenbach, Andreas Scherz, Justine Schlappa, Markus Scholz, Jan O. Schunck, Kiana Setoodehnia, Christian Stamm, Simone Techert, Sam M. Vinko, Heiko Wende, Alexander A. Yaroslavtsev, Zhong Yin, Martin Beye. 2022-11-30. Electron Dynamics at High-Energy Densities in Nickel from Non-linear Resonant X-ray Absorption Spectra. https://doi.org/10.1063/4.0000206

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