Even-symmetric Hall signal in perpendicular/in-plane magnetic anisotropy multilayers

The magnetic coupling between perpendicular magnetic anisotropy (PMA) and in-plane magnetic anisotropy (IMA) films plays a crucial role in achieving field-free magnetization switching driven by spin-orbit torque (SOT). In this study, we report an even-symmetric Hall magnetoresistance signal in IMA/PMA multilayers, which is attributed to the planar Hall effect and the emergence of an out-of-plane secondary easy axis by interlayer magnetic coupling. Field-free magnetization switching is achieved in the IMA/PMA multilayers through interlayer magnetic coupling. Additionally, shifts in SOT-driven magnetization switching curves are observed, arising from the nonparallel arrangement between the magnetic moments of the IMA layer and the applied pulse current. These findings deepen the understanding of interlayer coupling in IMA/PMA systems and hold significant implications for the development of SOT-based spintronic devices.