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arXiv · 0907.5574

Two inequivalent sublattices and orbital ordering in MnV2O4 studied by 51V NMR

S. -H. Baek·N. J. Curro·K. -Y. Choi·A. P. Reyes·P. L. Kuhns·H. D. Zhou·C. R. Wiebe
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Abstract

We report detailed 51V NMR spectra in a single crystal of MnV2O4. The vanadium spectrum reveals two peaks in the orbitally ordered state, which arise from different internal hyperfine fields at two different V sublattices. These internal fields evolve smoothly with externally applied field, and show no change in structure that would suggest a change of the orbital ordering. The result is consistent with the orbital ordering model recently proposed by Sarkar et al. [Phys. Rev. Lett. 102, 216405 (2009)] in which the same orbital that is a mixture of t_2g orbitals rotates by about 45$^\circ$ alternately within and between orbital chains in the I4_1/a tetragonal space group.

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S. -H. Baek, N. J. Curro, K. -Y. Choi, A. P. Reyes, P. L. Kuhns, H. D. Zhou, C. R. Wiebe. 2009-10-09. Two inequivalent sublattices and orbital ordering in MnV2O4 studied by 51V NMR. https://doi.org/10.1103/physrevb.80.140406

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