Spin-motive force due to magnetic domain wall motion in shaped nanostripes

Ieda, Junichi   ; Yamane, Yuta; Oe, Junichiro*; Maekawa, Sadamichi

In magnetic nanostructures, there is a correction to Faraday's law of induction. The effect, which is called as a spin-motive force, has been demonstrated in magnetic domain wall (DW) motion and an electron transport through magnetic nanoparticles. In such experiments, however, magnetization dynamics is driven by applied magnetic fields. Instead, by using a shaped magnetic nanostripe, the generation of spin-motive force without external driving forces has been proposed. We perform numerical calculations for the proposal. For a magnetic nanostripe designed to have two asymmetrical notches, a DW can be trapped at the notches lowering its surface energy. We apply a short pulse of a magnetic field for the DW to overcome the intermediate energy barrier between two notches. Then the DW is displaced automatically to the next notch discharging its magnetic energy via spin-motive force. We combine micromagnetic simulations and calculation of the spin-motive force to analyze this system.