Perturbative calculation of the spin-wave dispersion in a disordered double-exchange model

T. Semba; T. Fukui

doi:10.1143/jpsj.73.2646

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Perturbative calculation of the spin-wave dispersion in a disordered double-exchange model

T. Semba·T. Fukui

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Abstract

We study the spin-wave dispersion of localized spins in a disordered double-exchange model using the perturbation theory with respect to the strength of the disorder potential. We calculate the dispersion upto the next-leading order, and extensively examine the case of one-dimension. We show that in that case, disorder yields anomalous gapped-like behavior at the Fermi wavenumber of the conduction electrons.

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T. Semba, T. Fukui. 2004-06-05. Perturbative calculation of the spin-wave dispersion in a disordered double-exchange model. https://doi.org/10.1143/jpsj.73.2646

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