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.
@article{arxiv.0711.1844,
title = {Magnetic and orbital ordering in the spinel MnV2O4},
author = {V. O. Garlea and R. Jin and D. Mandrus and B. Roessli and Q. Huang and M. Miller and A. J. Schultz and S. E. Nagler},
journal= {arXiv preprint arXiv:0711.1844},
year = {2009}
}