Stack structure and temperature dependence of spin-orbit torques in heterostructures with antiferromagnetic PtMn

Abstract

We evaluate the stack structure and temperature dependence of the spin–orbit torques (SOTs) in metallic antiferromagnet (AFM)/ferromagnet (FM) PtMn/CoFeB heterostructures using an extended harmonic Hall measurement. We show that PtMn/CoFeB exhibits sizable Slonczewski-like and fieldlike SOTs whose magnitude is comparable to that of heterostructures with nonmagnetic heavy metals like Pt or Ta. We also find that the SOTs in our PtMn/CoFeB structures are virtually constant with temperature. The findings will offer clues to understand the generation mechanism of SOTs in AFM/FM systems and pave the way for nonvolatile memory and neuromorphic computing applications.