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arXiv · 1802.04336

Ab initio model of optical properties of two-temperature warm dense matter

Bastian Holst·Vanina Recoules·Stephane Mazevet·Marc Torrent·Andrew Ng·Zhijiang Chen·Sean E. Kirkwood·V. Sametoglu·M. Reid·Ying Y. Tsui
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Abstract

We present a model to describe thermophysical and optical properties of two-temperature systems consisted of heated electrons and cold ions in a solid lattice that occur during ultrafast heating experiments. Our model is based on ab initio simulations within the framework of density functional theory. The optical properties are obtained by evaluating the Kubo-Greenwood formula. By applying the material parameters of our ab initio model to a two-temperature model we are able to describe the temperature relaxation process of femtosecond-laser-heated gold and its optical properties within the same theoretical framework. Recent time-resolved measurements of optical properties of ultrafast heated gold revealed the dynamics of the interaction between femtosecond laser pulses and solid state matter. Different scenarios obtained from simulations of our study are compared with experimental data [Chen, Holst, Kirkwood, Sametoglu, Reid, Tsui, Recoules, and Ng, Phys. Rev. Lett. 110, 135001 (2013)].

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Bastian Holst, Vanina Recoules, Stephane Mazevet, Marc Torrent, Andrew Ng, Zhijiang Chen, Sean E. Kirkwood, V. Sametoglu, M. Reid, Ying Y. Tsui. 2018-02-12. Ab initio model of optical properties of two-temperature warm dense matter. https://doi.org/10.1103/physrevb.90.035121

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