FLUX MOTION DEPENDENCE OF RESISTIVE PROPERTIES IN SUPERCONDUCTING YBA2CU3O7-X THIN-FILMS

Abstract

Two models of flux motion are employed to study the resistive properties of superconducting YBa2Cu3O7-x thin films. The thermally activated flux creep model is employed to explain the dissipative behavior in the low resistivity region. However, when the resistivity is raised and approaches the normal state resistivity, the dissipative mechanism is gradually transferred from flux creep to flux flow. Based on the flux flow model, the upper critical field is estimated and shown as a function of temperature. In addition, a parallel resistivity circuit model is proposed to describe the transition behavior of the magnetic field dependence of resistivity versus current density characteristics.