Topologically Driven Spin-Orbit Torque in Dirac Matter

TL;DR

This paper reveals new spin-orbit torque mechanisms in magnetic graphene devices driven by topological edge states, with tunable effects depending on energy and spin-pseudospin entanglement, advancing understanding of topological spintronics.

Contribution

It introduces a novel topologically driven spin-orbit torque mechanism in Dirac materials, highlighting the role of edge states and energy-dependent effects.

Findings

Damping-like torque plateau in quantum anomalous Hall phase

Large damping-like torque at spin-split Dirac points

Tunable torques via spin-pseudospin entanglement

Abstract

We unveil novel spin-orbit torque mechanisms driven by topological edge states in magnetic graphene-based devices. Within the energy gap, a damping-like torque plateau emerges within the quantum anomalous Hall phase upon breaking particle-hole symmetry, while for energies at the spin-split Dirac points located within the bands, a large damping-like torque develops as a result of a vanishing Fermi contour. Such torques are tunable by the degree of spin-pseudospin entanglement dictated by proximity-induced spin-orbit coupling terms.