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Quantum behavior of Orbitals in Ferromagnetic Titanates: Novel Orderings and Excitations

Giniyat Khaliullin·Satoshi Okamoto
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Abstract

We investigate the collective behavior of orbital angular momentum in the spin ferromagnetic state of a Mott insulator with $t_{2g}$ orbital degeneracy. The frustrated nature of the interactions leads to an infinite degeneracy of classical states. Quantum effects select four distinct orbital orderings. Two of them have a quadrupolar order, while the other states show in addition weak orbital magnetism. Specific predictions are made for neutron scattering experiments which might help to identify the orbital order in YTiO$_3$ and to detect the elementary orbital excitations.

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Giniyat Khaliullin, Satoshi Okamoto. 2002-09-18. Quantum behavior of Orbitals in Ferromagnetic Titanates: Novel Orderings and Excitations. https://doi.org/10.1103/physrevlett.89.167201

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