Spin Hall Switching of the Magnetization in Ta/TbFeCo Structures with Bulk Perpendicular Anisotropy

TL;DR

This study investigates spin-orbit torques in Ta/TbFeCo structures with bulk perpendicular magnetic anisotropy, revealing strong anti-damping torque and a significant spin Hall angle, with negligible Rashba-like torque.

Contribution

First demonstration of spin-orbit torques in Ta/TbFeCo with bulk-PMA, highlighting the dominance of spin Hall effect over Rashba effect in this structure.

Findings

Strong anti-damping torque with a spin Hall angle of about 0.12

Magnetization switching confirmed with current pulses, ruling out Joule heating effects

Negligible Rashba-like torque indicating interface effects are minimal

Abstract

Spin-orbit torques are studied in Ta/TbFeCo patterned structures with a bulk perpendicular magnetic anisotropy (bulk-PMA) for the first time. The current-induced magnetization switching is investigated in the presence of a perpendicular, longitudinal, or transverse field. In order to rule out Joule heating effect, switching of the magnetization is also demonstrated using current pulses. It is found that the anti-damping torque correlated with spin Hall effect is very strong, and a spin Hall angle of about 0.12 is obtained. The field-like torque related with Rashba effect is negligible in this structure suggesting that the interface play a significant role in Rashba-like torque.