Current-induced magnetic domain wall motion in Pt/Co/Pd and Pd/Co/Pt structures with opposite sign of Dzyaloshinskii-Moriya interaction

The authors have investigated magnetic domain wall (DW) motion induced by electrical current in the perpendicularly magnetized Pt/Co/Pd and Pd/Co/Pt structures. In these systems, owing to the spin-orbit torque (SOT) and the interfacial Dzyaloshinskii-Moriya interaction (DMI), the DW moves in the current flowing direction. On the other hand, the threshold current density, DW velocity and magnitude of the DMI were found to be different between them even though the same combination of the materials are used. This results suggest that the SOT induced DW motion is significantly influenced by the stack sequence of the film.