Micromagnetic studies of cobalt microbars fabricated by nanoimprint lithography and electrodeposition

Micromagnetic and macromagnetic switching properties of cobalt bars with six different aspect ratios produced by electrodeposition of cobalt into patterns defined by nanoimprint lithography were studied. It was found that microbars in the demagnetized state formed configurations with closed magnetic flux. Magnetization along the long axis of the microbars resulted in a single-domain state of magnetization for microbars of all aspect ratios. In the remanent state, magnetization in microbars with smaller aspect ratios resumed the vortex configuration. Individual remanent curves, as well as the net remanent curve, were extracted from magnetic force microscopy images for microbars with all aspect ratios, and their agreement with the macroscopic magnetization measurements is discussed.