Spin-orbit torques in perpendicularly magnetized Ir₂₂Mn₇₈/Co₂₀Fe₆₀B₂₀/MgO multilayer

Abstract

The current-induced spin-orbit torques (SOTs) in the perpendicularly magnetized Ir22Mn78/Co20Fe60B20/MgO structures are investigated. The damping- and field-like torques are characterized using a harmonic technique. The spin Hall angle of Ir22Mn78 is determined to be θSHE = +0.057 ± 0.002. The SOT-driven magnetization switching is also demonstrated with the assistance of an external in-plane field. Furthermore, the magneto-optical Kerr effect imaging experiments show that the magnetization switching is realized through domain nucleation and domain wall motion. These results may promise potential practical applications in high-performance SOT devices based on the antiferromagnetic materials.