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arXiv · 1210.4776

GW study of the half-metallic Heusler compounds Co2MnSi and Co2FeSi

Markus Meinert·Christoph Friedrich·Günter Reiss·Stefan Blügel
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Abstract

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.

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Markus Meinert, Christoph Friedrich, Günter Reiss, Stefan Blügel. 2012-10-17. GW study of the half-metallic Heusler compounds Co2MnSi and Co2FeSi. https://doi.org/10.1103/physrevb.86.245115

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