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Spin Wave Theory of Double Exchange Ferromagnets

D. I. Golosov
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Abstract

We construct the 1/S spin-wave expansion for double exchange ferromagnets at T=0. It is assumed that the value of Hund's rule coupling, J_H, is sufficiently large, resulting in a fully saturated, ferromagnetic half-metallic ground state. We evaluate corrections to the magnon dispersion law, and we also find that, in contrast to earlier statements in the literature, magnon-electron scattering does give rise to spin wave damping. We analyse the momentum dependence of these quantities and discuss the experimental implications for colossal magnetoresistance compounds.

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D. I. Golosov. 2000-04-16. Spin Wave Theory of Double Exchange Ferromagnets. https://doi.org/10.1103/physrevlett.84.3974

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