Calculation of Phonon Satellites in Electron Spectral Functions

We describe a first principles approach for calculations of phonon satellites in the electron self-energy and spectral function. The method is based on cumulant expansion techniques [1] applied to the self-energy model of Eiguren and Ambrosch-Draxl [2] with the dynamical matrix and electron-phonon couplings obtained from ABINIT [3]. In particular, the electron-phonon couplings are calculated from the Eliashberg functions as in [4], and the phonon DOS is obtained from a many-pole/Lanczos representation of the phonon Green's function [5]. The method is illustrated with results for a number of systems.\\[4pt] [1] F. Aryasetiawan et al., Phys. Rev. Lett. 77, 2268 (1996).\\[0pt] [2] A. Eiguren and C. Ambrosch-Draxl, Phys. Rev. Lett. 101, 036402 (2008).\\[0pt] [3] X. Gonze et al., Comput. Materials Science 25, 478 (2002).\\[0pt] [4] S. Y. Savrasov and D. Y. Savrasov Phys. Rev. B 54, 16487 (1996).\\[0pt] [5] F. Vila et al., Phys. Rev. B 76, 014301 (2007).