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arXiv · 1205.1081

Orbital disorder induced by charge fluctuations in vanadium spinels

Yasuyuki Kato·Gia-Wei Chern·K. A. Al-Hassanieh·Natalia B. Perkins·C. D. Batista
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Abstract

Motivated by recent experiments on vanadium spinels, $A$V$_2$O$_4$, that show an increasing degree of electronic delocalization for smaller cation sizes, we study the evolution of orbital ordering (OO) between the strong and intermediate-coupling regimes of a multi-orbital Hubbard Hamiltonian. The underlying magnetic ordering of the Mott insulating state leads to a rapid suppression of OO due to enhanced charge fluctuations along ferromagnetic bonds. Orbital double-occupancy is rather low at the transition point indicating that the system is in the crossover region between strong and intermediate-coupling regimes when the orbital degrees of freedom become disordered.

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Yasuyuki Kato, Gia-Wei Chern, K. A. Al-Hassanieh, Natalia B. Perkins, C. D. Batista. 2012-05-04. Orbital disorder induced by charge fluctuations in vanadium spinels. https://doi.org/10.1103/physrevlett.108.247215

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