Edge effects on Dzyaloshinskii domain wall tilting

Abstract Interfacial Dzyaloshinskii-Moriya interaction (DMI) of a heavy metal (HM)/ferromagnetic (FM) metal heterostructure is vital to the current-induced fast domain wall motion. The tilting of the moving Dzyaloshinskii domian wall (DW) has been paid much attention. In this work, using the micromagnetic simulation, we find the DW tilting is originated from different initial DW velocity at two edges because of the initial antisymmetric magnetic structure at two edges. In the very early stage of DW motion, the DMI energy traps the DW motion at one edge. For a track whose width is smaller than a critical value, the edge effect plays a major role for DW tilting. This modifies the track width dependence of tilting angle and relaxation time derived from the collective coordinate method without considering edge effect. When the track is wide enough, a temporary vortex-like moment structure inside DW and variation of DW chirality at the edge appear in the process of generating DW tilting for reducing DMI and demagnetization energy.