10:45 AM - 11:00 AM
▼ [18a-D704-7] Research on Spin Hall Angle in CuBi Alloys by Spin Torque Measurement
Keywords:spintronics, CuBi, spin Hall angle
Cu has small spin-orbit interaction (SOI) and is known as a material with small spin Hall angle (SHA). Meanwhile, large SHA of -0.24 was measured in the Cu99.5Bi0.5 alloy at 10 K using a spin absorption method (Y. Niimi et al.). This observation signifies that a characteristic of the large SOI of Bi manifests in the alloy consisting mainly of a ubiquitous and low-resistive material, Cu, which is significant for practical applications such as spin-orbit torque (SOT) devices. In this study, we investigated the damping-like spin torque efficiency of Cu99.5Bi0.5 by using the second harmonic Hall measurement and spin torque ferromagnetic resonance measurement (STFMR) from a viewpoint of SOT device applications. From the theoretical fitting considering a thermal contribution, the SHA of the Cu99.5Bi0.5 is estimated to be about 0.1. In addition, it is confirmed that the sign of the SHA is positive from STFMR measurements.