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arXiv · 2208.02390

High-temperature self-energy corrections to x-ray absorption spectra

Tun S. Tan·J. J. Kas·S. B. Trickey·J. J. Rehr
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Abstract

Effects of finite-temperature quasiparticle self-energy corrections to x-ray absorption spectra are investigated within the finite-temperature quasiparticle local density GW approximation up to temperatures $T$ of order the Fermi temperature. To facilitate the calculations, we parametrize the quasiparticle self-energy using low-order polynomial fits. We show that temperature-driven decrease in the electron lifetime substantially broadens the spectra in the near-edge region with increasing $T$. However, the quasiparticle shift is most strongly modified near the onset of plasmon excitations.

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Tun S. Tan, J. J. Kas, S. B. Trickey, J. J. Rehr. 2022-08-04. High-temperature self-energy corrections to x-ray absorption spectra. https://doi.org/10.1103/physrevb.107.115122

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