Search

We report the current-induced domain-wall (CIDW) motion along the electron flow in the perpendicularly magnetized Co/Ni/Co structure sandwiched between the top and bottom Pt layers, observed by means of the Kerr microscope. As the lower Co thickness increases, the DW velocity for the electron flow is significantly increased, and also its motion becomes more stable irrespective of various current pulses. From the longitudinal field dependence of the DW velocity, it is found that the increase of the lower Co thickness increases a Dyzaloshinskii–Moriya interaction in the bottom Co/Pt interface, which results in the increase of the chiral spin torque, responsible for the increase of the DW velocity along the electron flow. [ABSTRACT FROM PUBLISHER]

Understanding the field-driven microscopic magnetization reversal in a disordered ferromagnetic (FM) film is a fundamentally intriguing issue for the application of a disorder-induced magnetic memory. We present the field dependence of the correlation between local coercivity and switching time in the FM films showing two typical reversal processes: wall-motion and nucleation dominant ones. As the applied field strength increases, the correlation coefficient in the wall-motion sample decreases, whereas the one in the nucleation sample holds nearly zero value. The change in the wall-motion sample is well explained by the transition of the magnetization reversal mechanism from a thermal activation reversal to a viscous motion. This paper shows that the magnetization reversal mechanism depending on the time scale as well as the materials has a strong influence on the correlation. [ABSTRACT FROM PUBLISHER]