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Spin Wave Theory of Double Exchange Magnets

D. I. Golosov
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Abstract

An isotropic half-metallic double exchange magnet with a direct superexchange coupling between the localized spins is studied within the spin-wave (1/S) expansion. The momentum dependence of the spin wave spectrum (including quantum corrections) in the ferromagnetic phase at T=0 is investigated. Based on the calculated spin wave spectrum of the canted state, it is shown that as long as the external magnetic field is not too strong, the double exchange -- superexchange competition does not result in a stabilization of a two-sublattice canted spin ordering.

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D. I. Golosov. 2000-02-24. Spin Wave Theory of Double Exchange Magnets. https://doi.org/10.1063/1.372528

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