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Spin-Orbital Entanglement and Violation of the Goodenough-Kanamori Rules

Andrzej M. Oles·Peter Horsch·Louis Felix Feiner·Giniyat Khaliullin
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Abstract

We point out that large composite spin-orbital fluctuations in Mott insulators with $t_{2g}$ orbital degeneracy are a manifestation of quantum entanglement of spin and orbital variables. This results in a dynamical nature of the spin superexchange interactions, which fluctuate over positive and negative values, and leads to an apparent violation of the Goodenough-Kanamori rules. [{\it Published in Phys. Rev. Lett. {\bf 96}, 147205 (2006).}]

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Andrzej M. Oles, Peter Horsch, Louis Felix Feiner, Giniyat Khaliullin. 2006-04-18. Spin-Orbital Entanglement and Violation of the Goodenough-Kanamori Rules. https://doi.org/10.1103/physrevlett.96.147205

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