Domain wall dynamics under nonlocal spin-transfer torque.

We study spin-diffusion effects within a continuously variable magnetization distribution, integrating with micromagnetics the diffusive model of Zhang and Li [Phys. Rev. Lett.

Effects of disorder and internal dynamics on vortex wall propagation.

Experimental measurements of domain wall propagation are typically interpreted by comparison to reduced models that ignore both the effects of disorder and the internal dynamics of the domain wall structure. Using micromagnetic simulations, we study vortex wall propagation in magnetic nanowires induced by fields or currents in the presence of disorder. We show that the disorder leads to increases and decreases in the domain wall velocity depending on the conditions.

Faster magnetic walls in rough wires.

In some magnetic devices that have been proposed, the information is transmitted along a magnetic wire of submicrometre width by domain wall (DW) motion. The speed of the device is obviously linked to the DW velocity, and measured values up to 1 km x s(-1) have been reported in moderate fields. Although such velocities were already reached in orthoferrite crystal films with a high anisotropy, the surprise came from their observation in the low-anisotropy permalloy.