FLUCTUATION CONDUCTIVITY OF A C-AXIS-ORIENTED YBA2CU3OY FILM PREPARED BY CHEMICAL VAPOR-DEPOSITION

The magnetoresistance of a highly c-axis-oriented chemical-vapor-deposition film of YBa2Cu3Oy was measured in the temperature range T(c) less than or similar to T less-than-or-equal-to 103 K for both the H parallel-to c axis and H perpendicular-to c axis. The analysis has been done on the basis of the superconducting fluctuation theory for the clean limit, and a good fit has been obtained for the temperature and the magnetic-field dependences of the magnetoconductance in the cases of the H parallel-to c axis and H perpendicular-to c axis. The results indicated that all of both orbital and Zeeman effects of the Aslamasov-Larkin and the Maki-Thompson terms contributed to the fluctuation conductivity. The superconducting coherence lengths were estimated to be xi(ab) (0) = 11. 5 angstrom and xi(c) (0) 3.2 angstrom in addition to the phase breaking time of the carrier tau(phi) = 8 X 10(-14) sec at 100 K.