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arXiv · 1309.6657

Ab-initio calculation of the effective on-site Coulomb interaction parameters for half-metallic magnets

Ersoy Sasioglu·Iosif Galanakis·Christoph Friedrich·Stefan Blügel
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Abstract

Correlation effects play an important role in the electronic structure of half-metallic (HM) magnets. In particular, they give rise to non-quasiparticle states above (or below) the Fermi energy at finite temperatures that reduce the spin polarization and, as a consequence, the efficiency of spintronics devices. Employing the constrained random-phase approximation (cRPA) within the full-potential linearized augmented-plane-wave (FLAPW) method using maximally localized Wannier functions, we calculate the strength of the effective on-site Coulomb interaction (Hubbard $U$ and Hund exchange $J$) between localized electrons in different classes of HM magnets considering: (i) \emph{sp}-electron ferromagnets in rock-salt structure, (ii) zincblende 3\emph{d} binary ferromagnets, as well as (iii) ferromagnetic and ferrimagnetic semi- and full-Heusler compounds.

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Ersoy Sasioglu, Iosif Galanakis, Christoph Friedrich, Stefan Blügel. 2013-09-25. Ab-initio calculation of the effective on-site Coulomb interaction parameters for half-metallic magnets. https://doi.org/10.1103/physrevb.88.134402

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