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arXiv · 2002.05561

Understanding XANES spectra of two-temperature warm dense copper using ab initio simulation

N. Jourdain·V. Recoules·L. Lecherbourg·P. Renaudin·F. Dorchies
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Abstract

Using ab initio molecular-dynamics simulations combined with linear-response theory, we studied the x-ray absorption near-edge spectra (XANES) of a two-temperature dense copper plasma. As the temperature increases, XANES spectra exhibit a pre-edge structure balanced by a reduction of the absorption just behind the edge. By performing systematic simulations for various thermodynamic conditions, we establish a formulation to deduce the electronic temperature Te directly from the spectral integral of the pre-edge that can be used for various thermodynamic conditions encountered in a femtosecond heating experiment where thermal non equilibrium and expanded states have to be considered.

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N. Jourdain, V. Recoules, L. Lecherbourg, P. Renaudin, F. Dorchies. 2020-02-13. Understanding XANES spectra of two-temperature warm dense copper using ab initio simulation. https://doi.org/10.1103/physrevb.101.125127

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