ACTIVATION-ENERGY FOR VORTEX MOTION IN ANISOTROPIC SUPERCONDUCTORS

We study the transport properties of highly anisotropic superconductor s with different kinds of topological disorder using Josephson-junctio n networks. The model describes a stack of weakly coupled superconduct ing planes in the presence of an external magnetic field perpendicular to them. At low temperatures the resistivities for current flowing pe rpendicularly and parallel to the external field show a thermally acti vated behavior. For systems with point defects, the activation energy is the same for the two components of the resistivity, while in system s with columnar defects they may be different. The results are interpr eted in terms of a simple model and compared with experimental results . [S0163-1829(98)05913-X].