Effect of Enhanced Damping Due to Spin-Motive Force on Field-Driven Domain Wall Motion

Temporal and spatial variation of magnetization generates an additional damping torque due to spin-motive force. We performed semi-one-dimensional (1-D) and two-dimensional (2-D) micromagnetic simulations to investigate effect of the additional damping on the field-driven transverse wall dynamics in a magnetic nanowire. At the magnetic field above the Walker breakdown field, the additional damping due to the spin-motive force causes an increase of domain wall velocity. In semi-1-D model, the amount of increased domain wall velocity is linearly proportional to the external magnetic field as predicted by theory. However, in 2-D model, it is inversely proportional to the field owing to the periodic injection of antivortex.