Interaction between a vortex line and uneven surface of type-II superconductor

The interaction between a cylindrical (with arbitrary profile) superconductor boundary and a vortex filament parallel to it is investigated. It is shown that a marked drop in the Bean - Livingston potential barrier may occur at definite points of the profile of an uneven bound-ary (due to a local increase in the surface current density). Even in those cases in which the characteristic scale of the distortions is small by comparison with the depth of penetration, the superheating field of the Meisner state may drop down to values on the order of $H_cϰ^{-1/2}$.