Drastic emergence of huge negative spin-transfer torque in atomically thin Co layers

Abstract

Current-induced domain wall (DW) motion has drawn great attention in the last decades as the key operational principle of emerging magnetic memory devices. As the major driving force of the current-induced DW motion, the spin-orbit torque (SOT) on chiral DWs has been proposed and extensively studied nowadays. However, we demonstrate here that there exists another driving force, which is larger than the SOT in ultra-thin Co films. Moreover, the direction of the present force is found to be opposite to the prediction of the spin-transfer torque (STT), resulting in the DW motion along the current direction. The symmetry of the force and its peculiar dependence on the DW structure suggest that the present force is, most likely, attributed to considerable enhancement of the nonadiabatic STT with a negative spin polarization in atomically thin Co layers. These findings open a new pathway to enhance the overall spin torque efficiency-the critical parameter in emerging spintronic devices.

References in corpus (6)

• Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmion at room temperature
• Skyrmions at room temperature : From magnetic thin films to magnetic multilayers
• Determination of the Spin-Hall-Effect-Induced and the Wedged-Structure-Induced Spin Torque Efficiencies in Heterostructures with Perpendicular Magnetic Anisotropy
• High domain wall velocities induced by current in ultrathin Pt/Co/AlOx wires with perpendicular magnetic anisotropy
• Asymmetric magnetic bubble expansion under in-plane field in Pt/Co/Pt: effect of interface engineering
• Chiral damping of magnetic domain walls

Cited by in corpus (9)

• Modification of Dzyaloshinskii-Moriya interaction stabilized domain wall chirality by driving currents
• Universality of Dzyaloshinskii-Moriya interaction effect over domain-wall creep and flow regimes
• Quantitative agreement of Dzyaloshinskii-Moriya interactions for domain-wall motion and spin-wave propagation
• Magnetic Domain-Wall Tilting due to Domain-Wall Speed Asymmetry
• Role of an additional interfacial spin-transfer torque for current-driven skyrmion dynamics in chiral magnetic layers
• Alternative understanding of the skyrmion Hall effect based on one-dimensional domain wall motion
• Angle-dependence and optimal design for magnetic bubblecade with maximum speed
• Chirality-induced Antisymmetry in Magnetic Domain-Wall Speed
• Wide-Range Probing of Dzyaloshinskii-Moriya Interaction