X-ray photoemission electron microscopy investigation of magnetic thin film antidot arrays

Periodic square arrays of antidots in 10 nm-thick cobalt films have been investigated with antidot periods, p, ranging from 2 μm down to 200 nm and various ratios of antidot size to antidot separation, w/d. For p=2 μm, the extent of modification of the thin film magnetic domain structure increases with increasing w/d, forming domains pinned diagonally between antidots for w/d⩾0.2 and resulting in a two-dimensional periodic checked domain contrast commensurate with the antidot lattice for w/d⩾0.9. As p is decreased while maintaining d≈w, we observe a dramatic change in the magnetic domain configuration at p=400 nm resulting in chains of magnetic domains running parallel to the intrinsic hard axis and with lengths corresponding to a multiple of the antidot period.