A STUDY OF THE MOTION OF FLUX LINES IN YBA2CU3O7-DELTA EPITAXIAL FILM

We have studied the motion of flux lines in YBa2Cu3O7-delta epitaxial film using the Hall effect and the broadening of the resistance-temperature curves (R-T curves) in a magnetic field. From the broadened R-T curves we obtained the exponential relation between the activation energy for flux creep and the magnetic field. In the measurement of the Hall coefficient R(H) we discovered anomalous behavior of the Hall effect corresponding to the broadening of the R-T curves. We have also interpreted the changes in the R-T curves and the R(H)-T curves using a vortex-glass model and explored the various aspects of flux motion.