EFFECTS OF DIMENSIONAL CROSSOVER ON ANISOTROPIC PINNING BEHAVIORS IN A MODEL HIGH-TC SUPERCONDUCTORS - YBCO (PRXY1-X)BCO SUPERLATTICES/

Superlattices of one unit-cell thick YBCO layers with (PrxY1-x)BCO wer e fabricated as a model system to study the effects of magnetic coupli ng on anisotropic pinning behaviors in high-T(c) superconductors. A 3D to 2D crossover was observed when the sample was transformed from an S/S' to an S/N structure by increasing the temperature without changin g the microscopic structure. The results demonstrate the significance of the dimensionality to the flux pinning in these materials with laye red structures.