• Vries, M. A. De
• Bos, J.-W. G.
• Mclaughlin, Abbie

Abstract

<p>We report on the unconventional magnetism in the cubic B-site ordered double perovskite Ba2YMoO6, using ac and dc magnetic susceptibility, heat capacity and muon spin rotation. No magnetic order is observed down to 2 K while the Weiss temperature is similar to - 160 K. This is ascribed to the geometric frustration in the lattice of edge-sharing tetrahedra with orbitally degenerate Mo5+ s = 1/2 spins. Our experimental results point to a gradual freezing of the spins into a disordered pattern of spin singlets, quenching the orbital degeneracy while leaving the global cubic symmetry unaffected, and providing a rare example of a valence bond glass.</p>

Topics

• perovskite
• impedance spectroscopy
• glass
• glass
• susceptibility
• quenching
• heat capacity