ELECTROMAGNETIC PINNING OF VORTICES ON DIFFERENT TYPES OF DEFECTS

We consider the general case of vortex interaction with elliptic hollo w cylinder at a distances smaller than the London penetration depth. F or the first time, the analytical solution of this problem is obtained , which permits us to treat the case of a vortex near the insulating s trip of finite length inside the superconductor. Our results are appli cable to superconducting films with regular arrays of defects like ell iptic holes (antidots) or segments (antisegments). It turns out that t he interaction is basically governed by the largest dimension of the d efect. We analyze how the collection of defects weakens the intervorte x interaction and makes it anisotropic. The solution of the problem of vortex interaction with a cylindrical hole in anisotropic superconduc tor is obtained as well. Finally, we demonstrate how the surface defec ts suppress the field of the vortex entrance. This effect is very impo rtant for layered superconductors. (C) 1998 Elsevier Science B.V.