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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Khaliullin, G., Kilian, R. (2001). Orbital Dynamics: the Origin of Anomalous Magnon Softening in Ferromagnetic Manganites. In: Bonča, J., Prelovšek, P., Ramšak, A., Sarkar, S. (eds) Open Problems in Strongly Correlated Electron Systems. NATO Science Series, vol 15. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0771-9_24
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DOI: https://doi.org/10.1007/978-94-010-0771-9_24
Publisher Name: Springer, Dordrecht
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