Evidence of magnetization switching by anomalous spin Hall torque in NiFe

Abstract

Recently the anomalous Hall effect was predicted as a possible mechanism to produce magnetization-dependent spin current. Here we have applied NiFe/Ru/perpendicular magnetic multilayers and a specific geometry to demonstrate magnetization switching driven by anomalous spin-orbit torque resulting from the bulk anomalous Hall effect. The anomalous spin Hall torque of NiFe is strong enough not only to switch the magnetization of perpendicular Co but also leads to opposite switching chirality compared with the ordinary spin Hall torque. This work confirmed the existence of a strong anomalous spin Hall torque due to anomalous Hall effect, which may lay a foundation to develop spin-orbit torque devices free of heavy metals.