Exchange bias, a shift in the hysteresis loop of a ferromagnet arising from interfacial exchange coupling between adjacent ferromagnetic (FM) and antiferromagnetic (AFM) layers, is an integral part of spintronic devices. Here, we show that spin–orbit torque (SOT) generated from spin current, a promising approach to switch the ferromagnetic magnetization of next-generation magnetic random-access memory, can also be used to manipulate the exchange bias. Applying current pulses to a Pt/Co/IrMn perpendicular magnetized trilayer causes concurrent switching of ferromagnetic magnetization and exchange bias. Using time-resolved magneto-optical Kerr microscopy, we further show that the FM as well as exchange bias can be either partially or completely switched by sub-nanosecond current pulses, which enables us to achieve well controlled multi-levels. Combing electrical and spectroscopic analysis, we also reveal that the spin configurations of bulk AFM can be manipulated by SOT.

Plus d'information :https://www.spintec.fr/seminar-spin-orbit-torque-switching-in-ferromagnetic-antiferromagnetic-systems/​