Edge effects on the high-frequency dynamics of Dzyaloshinskii domain walls

Chiral domain walls (DWs) in perpendicularly magnetized nanotracks (PMNTs) with interfacial Dzyaloshinskii-Moriya interaction (DMI) have become the primary objects of theoretical and experimental investigation due to their technological suitability in spintronic nanodevices. In this work, sway mode, a periodic dislocation of DWs, is found in a PMNT with a strong DMI under a high-frequency out-of-plane alternating magnetic field using micromagnetic simulation. This sway mode is out of prediction by the traditional collective coordinate method without considering edge effects. It is originated from DMI-related antisymmetric tilting of moments at two track edges, which results in inhomogeneous precession of moments throughout the DW under an out-of-plane alternating magnetic field. This work demonstrates the important role of edge effects to the dynamics of DWs with a strong DMI.