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Orbital order out of spin disorder: How to measure the orbital gap

G. Khaliullin·R. Kilian
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Abstract

The interplay between spin and orbital degrees of freedom in the Mott-Hubbard insulator is studied by considering an orbitally degenerate superexchange model. We argue that orbital order and the orbital excitation gap in this model are generated through the order-from-disorder mechanism known previously from frustrated spin models. We propose that the orbital gap should show up indirectly in the dynamical spin structure factor; it can therefore be measured using the conventional inelastic neutron scattering method.

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G. Khaliullin, R. Kilian. 1999-04-22. Orbital order out of spin disorder: How to measure the orbital gap. https://doi.org/10.1088/0953-8984%2F11%2F48%2F333

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