Manipulating antiferromagnetic interfacial states by spin-orbit torques

Abstract

We systematically investigated the manipulation of antiferromagnetic interfacial states through current-induced spin-orbit torques (SOT) in the $\mathrm{Pt}/\mathrm{Co}/{\mathrm{Ir}}_{25}{\mathrm{Mn}}_{75}(\mathrm{Ir}\text{\ensuremath{-}}\mathrm{Mn})$ system with varying Ir-Mn or Co thickness. The high tunability of antiferromagnetic interfacial states, that the antiferromagnetic interfacial spins gradually switched from upward to downward or vice versa by SOT, was achieved for the samples with ${t}_{\mathrm{IrMn}}\ensuremath{\ge}4\mathrm{nm}$, whereas the switching ability of antiferromagnetic interfacial spins via SOT under a perpendicular field or a longitudinal field was different, which was attributed to the influence from partial canted interfacial spins. Moreover, the interfacial spins of Ir-Mn layer can be also effectively tuned by SOT across Ru layer in the Pt/Co/Ru/Ir-Mn system, where the exchange coupling between Co and Ir-Mn decreased with increasing the thickness of the Ru layer. Our work provides a comprehensive understanding for manipulating antiferromagnetic interfacial states via SOT, which will promote innovative designs for antiferromagnetic spintronic devices.