Field-Free Spin-Orbit-Torque Switching in Co / Pt / Co Multilayer with Mixed Magnetic Anisotropies

As spintronics continues its march to replace conventional electronics, spin-orbit-torque (SOT) -induced magnetization switching attracts much attention, due to its relatively low switching current density, and scalability. SOT requires the breaking of time-reversal symmetry, and is typically assisted by an external magnetic field, or additional antiferromagnetic layers in a device. However, this study presents SOT-driven switching $w\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}h\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}u\phantom{\rule{0}{0ex}}t$ an external field, in multilayers consisting of two ferromagnetic Co layers with mixed anisotropies, separated by a Pt spacer acting as a source of spin current. This structure has potential in particular for applications in neuromorphic computing.