Determination of domain wall resistance in a cobalt thin film by thickness modulation.

Inspired by a well-known fact that the magnetic coercivity of a thin film has a strong dependence on its thickness, we have fabricated a 5×60 μm and 30 nm thick cobalt (Co) strip with thickness modulation along its long axis. The modulation period of 700 nm with a depth of 8 nm was prepared by a focused ion beam. From magnetic force microscope images, we observed an induced magnetic anisotropy along the short axis of the strip. By comparing out-of-plane magnetoresistance measurements in two magnetic remnant states, we extracted a positive domain wall resistance of 0.03 Ω, corresponding to 0.14% magnetoresistance (MR) in a Co thin film. [ABSTRACT FROM AUTHOR]