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Orbital Ordering and Orbital Fluctuations in Transition Metal Oxides

Andrzej M. Oles
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Abstract

We summarize some characteristic features of the frustrated magnetic interactions in spin-orbital models adequate for cubic transition metal oxides with orbital degeneracy. A generic tendency towards dimerization, found already in the degenerate Hubbard model, is confirmed for $t_{2g}$ but not for $e_g$ systems. In the $t_{2g}$ case the quantum orbital fluctuations are more pronounced and contribute to a stronger competition between different magnetic and orbital states. Therefore the orbital liquid states exist in some undoped $t_{2g}$ systems, while in the manganites such states can be triggered only by doping.

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Andrzej M. Oles. 2003-03-06. Orbital Ordering and Orbital Fluctuations in Transition Metal Oxides. https://doi.org/10.1002/pssb.200301667

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