engleski

Sign Change of Spin-Orbit Torque in Pt/NiO/CoFeB Structures

Antiferromagnetic insulators have recently been proved to support spin current efficiently. Here, we report the damping-like spin- orbit torque (SOT) in Pt / NiO / CoFeB has a strong temperature dependence and reverses the sign below certain temperatures, which is different from the slight variation with temperature in the Pt / CoFeB bilayer. The negative damping-like SOT at low temperatures is proposed to be mediated by the magnetic interactions that tie with the “exchange bias” in Pt / NiO / CoFeB, in contrast to the thermal-magnon-mediated scenario at high temperatures. Our results highlight the promise to control the SOT through tuning the magnetic structure in multilayers.

spintronics, spin torque, spin current, antiferromagnets, magnetic multilayers

nije evidentirano