Quasiparticle spectra of potentially half-metallic Co2MnSi and Co2FeSi Heusler compounds have been calculated within the one-shot GW approximation in an all-electron framework without adjustable parameters. For Co2FeSi the many-body corrections are crucial: a pseudogap opens and good agreement of the magnetic moment with experiment is obtained. Otherwise, however, the changes with respect to the density-functional-theory starting point are moderate. For both cases we find that photoemission and x-ray absorption spectra are well described by the calculations. By comparison with the GW density of states, we conclude that the Kohn-Sham eigenvalue spectrum provides a reasonable approximation for the quasiparticle spectrum of the Heusler compounds considered in this work.
@article{arxiv.1210.4776,
title = {GW study of the half-metallic Heusler compounds Co2MnSi and Co2FeSi},
author = {Markus Meinert and Christoph Friedrich and Günter Reiss and Stefan Blügel},
journal= {arXiv preprint arXiv:1210.4776},
year = {2013}
}