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Theory for spin and orbital orderings in high temperature phase in $YVO_3$

Theja N. De Silva·Anuvrat Joshi·Michael Ma·Fu Chun Zhang
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Abstract

Motivated by the recent neutron diffraction experiment on $YVO_3$, we consider a microscopic model where each $V^{3+}$ ion is occupied by two 3d electrons of parallel spins with two fold degenerate orbital configurations. The mean field classical solutions of the spin-orbital superexchange model predicts an antiferro-orbital ordering at a higher temperature followed by a C-type antiferromagnetic spin ordering at a lower temperature. Our results are qualitatively consistent with the observed orbital phase transition at $\sim 200K$ and the spin phase transition at $\sim 114K$ in $YVO_3$.

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Theja N. De Silva, Anuvrat Joshi, Michael Ma, Fu Chun Zhang. 2003-09-13. Theory for spin and orbital orderings in high temperature phase in $YVO_3$. https://doi.org/10.1103/physrevb.68.184402

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