"Structure and magnetic properties of the pyrochlore iridate Y2Ir2O7"

M. C. Shapiro: Scott C. Riggs, M. B. Stone, C. R. de la Cruz, S. Chi, A. A. Podlesnyak, and I. R. Fisher; Phys. Rev. B , 06/26/12.

Additional Authors: Scott C. Riggs, M. B. Stone, C. R. de la Cruz, S. Chi, A. A. Podlesnyak, and I. R. Fisher

Abstract:

Neutron powder diffraction and inelastic measurements were performed examining the 5d pyrochlore Y2Ir2O7. Temperature-dependent measurements were performed between 3.4 K and 290 K, spanning the magnetic transition at 155 K. No sign of any structural or disorder-induced phase transition was observed over the entire temperature range. In addition, no sign of magnetic long-range order was observed to within the sensitivity of the instrumentation. These measurements do not rule out long-range magnetic order, but the neutron-powder-diffraction structural refinements do put an upper bound for the ordered iridium moment of ∼0.2 μB/Ir (for a magnetic structure with wave vector Q≠0) or ∼0.5 μB/Ir (for Q=0).