Computational simulation of flux trapping and vortex pinning in type-II superconductors

Effects of pointwise thickness variations and material inhomogeneities in t he dynamics of vorticies are investigated by means of appropriately formula ted Time-Dependent Ginzburg-Landau (TDGL) based models for inhomogeneous th in films having constant thickness and homogeneous thin films having variab le thickness. The resulting models are solved numerically using a nonstanda rd finite difference method for spatial discretization and a modified forwa rd Euler method for temporal discretization. In particular, vortex pinning and flux trapping phenomena in both types of films are investigated. Our nu merical simulations indicate that the dynamics of vortices are mostly affec ted by inhomogeneities introduced in the chemical composition of a material as compared to variations introduced in thickness of the material. (C) 199 9 Elsevier Science Inc. All rights reserved.