Abstract
Oxides containing iridium ions display a range of magnetic and conducting properties that depend on the delicate balance between interactions and are controlled, at least in part, by the details of the crystal architecture. We have used muon spin rotation (SR) to study the local field in four iridium oxides, CaIrO, CaIrO, SrIrO, and SrIrO, which show contrasting behavior. Our SR data on CaIrO and CaIrO are consistent with conventional antiferromagnetism where quasistatic magnetic order develops below and 7.84(7) K, respectively. A lower internal field is observed for CaIrO, as compared to CaIrO, reflecting the presence of both Ir and Ir ions and resulting in a more magnetically dilute structure. Muon precession is only observed over a restricted range of temperature in SrIrO, while the Mott insulator SrIrO displays more complex behavior, with the SR signal containing a single, well-resolved precession signal below K, which splits into two precession signals at low temperature following a reorientation of the spins in the ordered state.
- Received 16 December 2010
DOI:https://doi.org/10.1103/PhysRevB.83.094416
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