Current-Induced Modulation of Coercive Field in the Ferromagnetic Oxide SrRuO3

We investigated the coercive field H_c for domain wall (DW) motion as a function of the current I in the ferromagnetic oxide SrRuO₃, a model system with narrow DWs for fabricating high-density spintronics devices. The DW is moved by I in the direction of the current, and H_c is modulated linearly in I. This linear relationship is consistent with an effective magnetic field H_eff driving the DW. The direction of DW motion and the magnitude of H_eff are well described by a model based on the field-like torque arising from the spin relaxation of conduction electrons in the DW.