First-principles calculation of K absorption edge of warm dense aluminum

Shifts of K absorption edge of warm dense aluminum with respect to the change of thermodynamic conditions are calculated using first-principles methods\footnote{S. Zhang, S. Zhao, W. Kang, P. Zhang, and X. T. He, Phys. Rev. B \textbf{93}, 115114 (2016)}, which shows good agreement with the experimental measurements\footnote{A. Benuzzi-Mounaix, F. Dorchies, V. Recoules, F. Festa, O. Peyrusse, A. Levy, A. Ravasio, T. Hall, M. Koenig, N. Amadou, E. Brambrink, and S. Mazevet, Phys. Rev. Lett. \textbf{107}, 165006 (2011)}. Improvement is achieved with a careful consideration of the effect of core electrons. The shift of K edge is revealed more sensitive to the change of temperature than to that of density in the warm dense region, which suggests K edge shift a good temperature indicator. The flattening point of the K edge shift at higher temperature is attributed to the thermal depletion of the M-band electrons.