Domain wall propagation in magnetic nanowires by spin-polarized current injection

We demonstrate movement of a head-to-head domain wall through a magnetic nanowire of permalloy (Ni81Fe19) simply by passing an electrical current through the domain wall and without any external magnetic field applied. The effect depends on the sense and magnitude of the electrical current and allows direct propagation of domain walls through complex nanowire shapes, contrary to the case of magnetic-field–induced propagation. The efficiency of this mechanism has been evaluated and the effective force acting on the wall has been found equal to 0.44 × 10−9 N A−1.