Critical current density of domain wall oscillation due to spin-transfer torque

Abstract

The domain wall oscillation due to spin-transfer torque was studied by numerically solving the Landau-Lifshitz-Gilbert (LLG) equation. For a domain wall whose rotation angle θmax is less than 180°, we found the existence of the critical current density above which the magnetization dynamics are induced. We studied the dependence of the critical current density on the rotation angle θmax and found that the critical current density is proportional to 180° - θmax.