ac and dc current-induced motion of a 360 degrees domain wall

Abstract

he response of 360° [360 degrees]domain walls in narrow magnetic stripes to applied dc and ac currents, investigated by micromagnetic simulation, differs qualitatively from the response of 180° [180 degrees] domain walls. The 360° [360 degrees] domain-wall velocity scales with a dc current but is independent of an applied magnetic field along the stripe. An annihilation process occurs at a critical dc current density that varies with the applied field. When a 360° [360 degrees] wall is perturbed, it oscillates at a characteristic frequency in the gigahertz range which is tunable by the applied magnetic field, and an ac current applied at half the characteristic frequency excites a resonant response.