paper

Disorder driven spin-orbital liquid behaviour in the BaXSbO materials

arXiv:1506.01845 · doi:10.1103/PhysRevLett.115.147202

Abstract

Recent experiments on the BaXSbO family have revealed materials that potentially realise spin- and spin-orbital liquid physics. However, the lattice structure of these materials is complicated due to the presence of charged X-Sb dumbbells, with two possible orientations. To model the lattice structure, we consider a frustrated model of charged dumbbells on the triangular lattice, with long-range Coulomb interactions. We study this model using Monte Carlo simulation, and find a freezing temperature, , at which the simulated structure factor matches well to low-temperature x-ray diffraction data for BaCuSbO. At we find a complicated ``branching'' structure of superexchange-linked X clusters, and show that this gives a natural explanation for the presence of orphan spins. Finally we provide a plausible mechanism by which such dumbbell disorder can promote a spin-orbital resonant state with delocalised orphan spins.

10 pages, 11 figures

References in corpus (6)

Cited by in corpus (20)