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Structural, orbital, and magnetic order in vanadium spinels

O. Tchernyshyov
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Abstract

Vanadium spinels (ZnV_2O_4, MgV_2O_4, and CdV_2O_4) exhibit a sequence of structural and magnetic phase transitions, reflecting the interplay of lattice, orbital, and spin degrees of freedom. We offer a theoretical model taking into account the relativistic spin-orbit interaction, collective Jahn-Teller effect, and spin frustration. Below the structural transition, vanadium ions exhibit ferroorbital order and the magnet is best viewed as two sets of antiferromagnetic chains with a single-ion Ising anisotropy. Magnetic order, parametrized by two Ising variables, appears at a tetracritical point.

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O. Tchernyshyov. 2004-07-21. Structural, orbital, and magnetic order in vanadium spinels. https://doi.org/10.1103/physrevlett.93.157206

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