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Considerations on the quantum double-exchange Hamiltonian

A. Weisse·J. Loos·H. Fehske
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Abstract

Schwinger bosons allow for an advantageous representation of quantum double-exchange. We review this subject, comment on previous results, and address the transition to the semiclassical limit. We derive an effective fermionic Hamiltonian for the spin-dependent hopping of holes interacting with a background of local spins, which is used in a related publication within a two-phase description of colossal magnetoresistant manganites.

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A. Weisse, J. Loos, H. Fehske. 2001-01-16. Considerations on the quantum double-exchange Hamiltonian. https://doi.org/10.1103/physrevb.64.054406

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