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Spin-orbital physics in the optical conductivity of quarter-filled manganites

Jan Bala·Peter Horsch
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Abstract

Using finite-temperature diagonalization we investigate the optical conductivity $σ(ω)$ and spin-orbital dynamics in the CE phase of half-doped manganites. We find $σ(ω)$ characterized by a broad spectrum with pronounced optical gap due to charge ordering induced by Coulomb and further neighbor Jahn-Teller interactions. With increasing temperature the conductivity shows a significant change over a wide energy range with a characteristic shift towards lower frequencies. In the low temperature CE phase we observe in-gap absorption due to combined orbiton-spin excitations.

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Jan Bala, Peter Horsch. 2005-03-01. Spin-orbital physics in the optical conductivity of quarter-filled manganites. https://doi.org/10.1103/physrevb.72.012404

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