Spin Order due to Orbital Fluctuations: Cubic Vanadates
Spin Order due to Orbital Fluctuations: Cubic Vanadates
We investigate the highly frustrated spin and orbital superexchange interactions in cubic vanadates. The fluctuations of ${t}_{2g}$ orbitals trigger a novel mechanism of ferromagnetic interactions between spins $S\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$ of ${\mathrm{V}}^{3+}$ ions along one of the cubic directions which operates already in the absence of Hund's rule exchange ${J}_{H}$, and leads …