Spin-orbit torque is a current-induced transfer of angular momentum from an atomic lattice to magnetic order. It is a promising mechanism to write magnetic memories and drive spin torque oscillators. Since its inception, the list of spin-orbit torque mechanisms has grown beyond the conventional spin Hall and Rashba-Edelstein mechanisms to include “unconventional” mechanisms, arising from spin and orbital current generation in ferromagnetic layers, nonmagnetic layers, and their interfaces. In this talk, we use micromagnetic, semiclassical, and first principles calculations to show that unconventional spin-orbit torques are potentially important for devices, from causing nonlocal spin torques in ferromagnetic trilayers to enabling large amplitude, easy-plane spin-orbit torque oscillators.
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