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Orbital Dynamics: The Origin of Anomalous Magnon Softening in Ferromagnetic Manganites

G. Khaliullin·R. Kilian
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Abstract

We study the renormalization of magnons by charge and coupled orbital-lattice fluctuations in colossal magnetoresistance compounds. The model considered is an orbitally degenerate double-exchange system coupled to Jahn-Teller active phonons. The modulation of ferromagnetic bonds by low-energy orbital fluctuations is identified as the main origin of the unusual softening of the zone-boundary magnons observed experimentally in manganites.

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G. Khaliullin, R. Kilian. 1999-06-03. Orbital Dynamics: The Origin of Anomalous Magnon Softening in Ferromagnetic Manganites. https://arxiv.org/abs/cond-mat/9904316

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