Fast and controllable switching in narrow ring nanomagnets

Abstract Using micromagnetic simulations we show that magnetization reversal in narrow rings can take place via a nucleation-free domain wall motion process when a field pulse is applied in the plane of the film and perpendicular to the net magnetization. Switching times in the order of 400 ps can be achieved with this approach. A lower bound for the depinning time of the domain walls and a small dependence of the domain wall velocity with the applied field are found.