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arXiv · 0711.1844

Magnetic and orbital ordering in the spinel MnV2O4

V. O. Garlea·R. Jin·D. Mandrus·B. Roessli·Q. Huang·M. Miller·A. J. Schultz·S. E. Nagler
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Abstract

Neutron inelastic scattering and diffraction techniques have been used to study the MnV2O4 spinel system. Our measurements show the existence of two transitions to long-range ordered ferrimagnetic states; the first collinear and the second noncollinear. The lower temperature transition, characterized by development of antiferromagnetic components in the basal plane, is accompanied by a tetragonal distortion and the appearance of a gap in the magnetic excitation spectrum. The low-temperature noncollinear magnetic structure has been definitively resolved. Taken together, the crystal and magnetic structures indicate a staggered ordering of the V d orbitals. The anisotropy gap is a consequence of unquenched V orbital angular momentum.

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V. O. Garlea, R. Jin, D. Mandrus, B. Roessli, Q. Huang, M. Miller, A. J. Schultz, S. E. Nagler. 2007-11-12. Magnetic and orbital ordering in the spinel MnV2O4. https://doi.org/10.1103/physrevlett.100.066404

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