Determination of the resistivity anisotropy of SrRu O3 by measuring the planar Hall effect

We have measured the planar Hall effect in epitaxial thin films of the itinerant ferromagnet SrRu O3 patterned with their current paths at different angles relative to the crystallographic axes. Based on the results, we have determined that SrRu O3 exhibits small resistivity anisotropy in the entire temperature range of our measurements (between 2 and 300 K); namely, both above and below its Curie temperature (150 K). Our results indicate that in addition to anisotropy related to the spontaneous magnetization, the resistivity anisotropy of SrRu O3 has an intrinsic, nonmagnetic source. We have found that the two sources of anisotropy have competing effects.