MAGNETIC PINNING BY PLANAR DEFECTS IN TYPE-II SUPERCONDUCTORS

The magnetic interaction between a vortex and a planar defect with a f inite width is studied using the London approximation. The penetration depth inside the defect is assumed to vary spatially and the vortex t o run parallel to the defect. It is found that the planar defect influ ences the field and current distributions of the vortex significantly. An interference effect appears as a result of the presence of two pla nar boundaries. When the vortex is situated near the planar defect. a large pinning force arises due to the redistribution of the circular c urrent around the vortex core. Both the pinning potential and the pinn ing force can be of the same order as those of the core pinning. The p inning force is largest when the width of the defect is nearly 4xi.