Switching of perpendicularly magnetized nanomagnets with spin-orbit torques in the absence of external magnetic fields

Abstract

A method of controlling a trajectory of a perpendicular magnetization switching of a ferromagnetic layer using spin-orbit torques in the absence of any external magnetic field includes: injecting a charge current Jthrough a heavy-metal thin film disposed adjacent to a ferromagnetic layer to produce spin torques which drive a magnetization M out of an equilibrium state towards an in-plane of a nanomagnet; turning the charge current Joff after tseconds, where an effective field experienced by the magnetization of the ferromagnetic layer His significantly dominated by and in-plane anisotropy H, and where M passes a hard axis by precessing around the H; and passing the hard axis, where His dominated by a perpendicular-to-the-plane anisotropy H, and where M is pulled towards the new equilibrium state by precessing and damping around H, completing a magnetization switching.