Real-time analysis of the spinmotive force due to domain wall motion

Ieda, Junichi   ; Maekawa, Sadamichi; Yamane, Yuta

Spinmotive force, which is induced by motion of a nonuniform magnetic nanostructure, reflects real time dynamics of the magnetization texture. Using numerical simulations we study the spinmotive force associated with domain wall motion and find that its dc component scales with an applied magnetic field even in a field range where the wall motion is no longer associated with periodic angular rotation of the wall magnetization. As the field is increased, spikes in the voltage signals start to appear, which are mainly associated with vortex core nucleation and annihilation. At high fields, the slope of the generated dc voltage with the applied field is expected to be only dependent on the spin polarization of conduction electrons and thus can be used to accurately determine the degree of spin polarization in various materials.