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Microstructural evolution with the change in thickness of superconducting YBa2Cu3O7-x films on single-crystal SrTiO3 substrates deposited by pulsed laser deposition was evaluated using different structural characterization tools. A noticeable degradation of crystallinity with the increased film thickness was detected. Nevertheless, a comprehensive relationship between the microstructure and the zero-field current-density can not be established solely based on the degradation of crystallinity. [ABSTRACT FROM AUTHOR]

The angular-dependent critical current density Jc in YBa2Cu3O7 films grown by pulsed laser deposition exhibit a sharp peak for magnetic field orientations near the ab plane, which arises front the combined effects of intrinsic pinning and extended defects parallel to the planes. An analysis of the temperature and field dependence of the height and width of this peak allows us to distinguish both contributions. We find that, in a film on single crystal substrate, the peak at low fields is due primarily to the extended defects, but at high fields it is dominated by intrinsic pinning. We compare these results with those of coated conductors with a larger density of ab-oriented correlated defects. We show a novel effect consisting in an inverse correlation between Jc and the power law exponent (N) of the I-V curves that only occurs In the intrinsic-pinning dominated regime, and we present an interpretation of its origin. [ABSTRACT FROM AUTHOR]