Skyrmion pinning by disk-shaped defects

High precision skyrmion pinning by an intentionally created magnetic structure is important in manipulation. Here, we consider various types of disks. Among other findings, clarify that, terms position and potential landscape, one needs to distinguish thin-wall skyrmions from thick-wall because fundamental differences. A wall prefers areas with a weaker exchange stiffness, larger DMI constant, or smaller anisotropy while core experiences only the anisotropy, not stiffness DMI. Depending on disk type, relative size (to skyrmion), can be pinned at symmetric (center) asymmetric (off-center) point disk. In case local energy minimum, thermal agitation depin skyrmion, lifetime follows Arrhenius law. Interestingly, when comparable size, deforms greatly such that will shrink expand fill whole These findings should for manipulations.