Rotational dynamics of paired nano-domain walls confined in an elliptical ring

We have investigated a way to control of rotary motion of paired domain walls in a ferromagnetic ring structure. A variation in the width and the curvature of the elliptical ring causes a spatial-dependent stability for the domain walls. In the absence of the external magnetic field, the domain walls tend to move to the stable positions. By applying linearly oscillating in-plane magnetic field the paired domain walls rotate in the direction which depends on the tilt angle of the in-plane field.