Vicinal substrate induced field-free spin–orbit torque switching and tunability of the Dzyaloshinskii–Moriya interaction in the CoPt layer

Spin–orbit torque (SOT)-induced magnetization switching is a key ingredient for electrically controlled spintronic devices. Crystal engineering offers an effective approach to tailor and optimize SOT efficiency. In this work, we demonstrate that a controllable anisotropic crystal distortion can be introduced by growing CoPt films on vicinal substrates, which enables full-range, field-free SOT switching of the CoPt layer. Moreover, the strength of the Dzyaloshinskii–Moriya interaction (DMI) can also be tuned by adjusting the substrate vicinality. With its simple structure, full-range switching capability, and tunable DMI, our findings are beneficial for the design of next-generation spintronic devices.