Domain wall based spin torque nano-oscillator in Z-type magnetic nanowire with perpendicular magnetic anisotropy

Abstract

A domain wall based spin torque nano-oscillator is a potential device for microwave generation because of its tunability of frequency, operation at room temperature, and integration with complementary metal-oxide-semiconductors. Here, we proposed and numerically demonstrated a spin nano-oscillator with domain wall steady oscillation in Z-type magnetic nanowires with perpendicular magnetic anisotropy by micromagnetic simulations. We find that the dynamical behavior of domain walls at Z-junctions is highly affected by the dimension of Z-junctions and current density. Three kinds of behaviors are found, i.e., damped oscillation, steady oscillation, and collapse. The observed steady oscillation can be used as spin torque nano-oscillators with a working frequency can approach 20 GHz. Our findings could enrich the investigation of spin torque nano-oscillators at high frequencies for novel microwave emitters.