Time: 2:00 pm
Venue: LeConte 402
Title: Discovery of Chiral Spin Order in Some Compounds
Abstract: Examination of the magnetic torque measurements in some iridates and in RuCl(3) suggests that they have chiral spin-order of the form
< Si · (Sj × Sk > .
Given an anisotropy so that two of the three spins in the order parameter lie in the plane, a cusp is expected in the energy when a magnetic ﬁeld B is applied in a direction approaching the normal to the plane. This leads to a discontinuity in Torque with a magnitude ∝ |B|3. This prediction has been tested in experiments.
Relation of the connection of chiral order to spin-liquids, to topological eﬀects expected, and to the nature of the ground state and excitations for deviations from a spin per site, will also be discussed.