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arXiv · 1403.2590

Spin Dependent Lifetimes and Spin-orbit Hybridization Points in Heusler Compounds

Steffen Kaltenborn·Hans Christian Schneider
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Abstract

We present an ab initio calculation of the k and spin-resolved electronic lifetimes in the half-metallic Heusler compounds Co(2)MnSi and Co(2)FeSi. We determine the spin-flip and spin-conserving contributions to the lifetimes and study in detail the behavior of the lifetimes around states that are strongly spin-mixed by spin-orbit coupling. We find that, for non-degenerate bands, the spin mixing alone does not determine the energy dependence of the (spin-flip) lifetimes. Qualitatively, the lifetimes reflect the lineup of electron and hole bands. We predict that different excitation conditions lead to drastically different spin-flip dynamics of excited electrons and may even give rise to an enhancement of the non-equilibrium spin polarization.

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Steffen Kaltenborn, Hans Christian Schneider. 2014-03-12. Spin Dependent Lifetimes and Spin-orbit Hybridization Points in Heusler Compounds. https://doi.org/10.1103/physrevb.89.115127

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