Determination of Domain Wall Depinning and Driving Currents in Doped Permalloy Structures

In this paper we investigate the domain wall pinning positions at parabolic pinning potentials in Gd doped wires. Increasing the Gd doping percentage favors the formation of vortex domain walls, shown to be due to an increase in the out of plane anisotropy, allowing the pinning of a vortex and a transverse domain wall in two similar parabolic pinning potentials. Using pulsed currents to investigate the difference in the depinning characteristics of these two domain wall types, we show that the current density required for steady domain wall motion is smaller than the current density required to set it in motion and estimate this difference to be of the order .