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Hole dynamics in spin and orbital ordered vanadium perovskites

Sumio Ishihara
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Abstract

Hole dynamics in spin and orbital ordered vanadates with perovskite structure is investigated. A mobile hole coupled to the spin excitation (magnon) in the spin G-type and orbital C-type (SG/OC) ordered phase, and that to the orbital excitation (orbiton) in the spin C-type and orbital G-type (SC/OG) one are formulated on an equal footing. The observed fragile character of the (SG/OC) order is attributed to the orbiton softening caused by a reduction of the taggered magnetic order parameter. It is proposed that the qualitatively different hole dynamics in the two spin-orbital ordered phases in vanadates can be probed by the optical spectra.

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Sumio Ishihara. 2004-08-18. Hole dynamics in spin and orbital ordered vanadium perovskites. https://doi.org/10.1103/physrevlett.94.156408

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