Decoupling between the superconducting layers in (YBa2Cu3O7)(24)/(PrBa2Cu3O7)(2) multilayer thin film

The temperature dependence of the resistivity of an epitaxial (YBa2Cu3O7)(2 4)/(PrBa2Cu3O7-delta)(2) multilayer thin film has been measured at low magn etic fields up to 1 T parallel and perpendicular to the c-axis and at a con stant field of 0.12 T for various angles. The results show that the PrBCO l ayers can trap the flux line for H parallel to ab and result in two-dimensi onal (2D) behavior for the tilted field. The activation energy shows a fiel d independent behavior in a field smaller than 0.12 T and a logarithmic fie ld behavior above this field. The angular dependence of the activation ener gy at H = 0.12 T reveals that the dissipation is only related to the perpen dicular field component, which is consistent with Kes' 2D pancake model. Th e coupling and decoupling between the YBCO layers were investigated. (C) 20 01 Elsevier Science B.V. All rights reserved.