Proposed controlled creation and manipulation of skyrmions with spin-orbit torque

Abstract

The physical mechanisms underlying current-driven skyrmion motion include the spin-transfer torque exerted by a spin-polarized horizontal electric current and the spin-orbit torque exerted by a perpendicular spin current. Each mechanism requires a specific sample geometry and structural configuration. Regarding current-induced skyrmion creation, skyrmions can be efficiently created at low current densities via spin-transfer torque when an electric current is applied to a nanotrack structure with a small notch. However, an effective and controlled method for skyrmion creation via spin-orbit torque in notched nanotracks has yet to be established. Here we theoretically propose a method for the creation, driving, and deletion of skyrmions in a three-terminal magnetic heterojunction with a notch. Our proposal offers valuable insights into the design of techniques for skyrmion creation and manipulation using spin-orbit torque, which is essential for technical applications of magnetic skyrmions as information carriers in next-generation spintronic memory devices.