Simulating the Maximum Domain Wall Speed in a Magnetic Nanowire

The dynamics of domain wall motion in permalloy nanowires have been simulated utilizing the Landau-Lifshitz-Gilbert (LLG) equation of motion. The simulation results are presented in terms of the domain wall speed for ranges of the Gilbert damping parameter alpha and nanowire width. The maximum domain wall speed is independent of alpha. The speed of the domain wall can be increased by increasing the nanowire width, but this lowers the critical field. For applied fields below the critical field, the wall moves uniformly along the wire and the speed of the wall increases with increases in the driving field. This behavior is consistent with current analytic models; however, the models overestimate both the value of the domain wall speed and the critical field