Domain Wall Pinning and Corresponding Energy Barrier in Percolated Perpendicular Medium

The domain wall pinning processes in a percolated perpendicular medium are studied using micromagnetic modeling. With a given nonmagnetic pinning site, the energy barrier of the pinned domain wall reaches a maximum when the domain wall width is about twice the size of the pinning site. For transitions in the percolated perpendicular medium, the energy barrier for the transition shift is sensitive to the pinning site spacing. Considering regularly distributed pinning sites with 4.7-nm center-to-center spacing, the energy barrier for the transition shift is about twice the energy barrier of the domain wall pinned by one pinning site. The domain stability in percolated perpendicular medium is also discussed with an analytic model