Reversal of Domain Wall Motion in Perpendicular Magnetized Tb-Fe-Co Nanowires

We studied the motion of magnetic domain walls (DWs) in SiO
₂
/TbFeCo/Pt (asymmetric) and Pt/TbFeCo/Pt (symmetric) nanowires. The reversed DW motion was observed in the asymmetric wire at zero field and room temperature. The reversed DW motion was attributed to the structural inversion asymmetry-induced spin-orbit torques from Pt/TbFeCo interface and Pt layer of the asymmetric wire. The DW velocity sign was again reversed when the current density is larger than 1.52 × 10
¹¹
A/m
²
which corresponds to threshold of Walker-breakdown current density.