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YBCO thin films grown on SrTiO3, yttria-stabilized zirconia (YSZ), and YSZ with CeO2 buffer layer, by pulsed laser deposition, were studied by high resolution x-ray diffraction, including Rocking curve, and Phi-scan. It is shown that the distortion of the thin films is different in the different substrates. The careful calculation of the cohesive energy of the thin films and substrates, especially considering the effect of the interaction of the YBCO and substrates, indicates there is a close relationship between the cohesive energy and the distortion of the films. Using it to explain the distortion is better than using mismatch.

The dynamic decay process of the remnant field and the thermally activated flux creep in the melt texture growth Y2BaCuO5and platinum doped YBa2Cu3O7bulk samples were directly observed. The doping effect of Y2BaCuO5and platinum on the trapped flux was clearly watched.

We report the transient differential reflectivity ΔR/R in Y1−x−yPrxCayBa2Cu3O7thin films. The transient differential reflectivity measurement reveals that the effect of Pr substitution for Y ions on the related Fermi level position is similar to that of the oxygen deficiency in YBa2Cu3O7-δsystem, however, it is different from the effect of divalent Ca substitution for Pr.

Using high resolution transmission electron microscopy (HRTEM) and scanning tunneling microscopy (STM) three different growth processes of the epitaxial YBCO films are observed: (1) the epitaxial YBCO layers nucleate on perfect substrates and lead to flat surfaces. (2) one-unit cell steps on the substrate surfaces developed to dislocations of the grown YBCO film. (3) on tilted substrates stacks of terraces are the main surface morphologies. These results are clearly demonstrated that the substrates have significant influence on the microstructure of the epitaxial YBCO films.

YBa2Cu3O7/Pr0.7Sr0.3MnO3/Ag sandwiches and YBa2Cu3O7/Pr0.7Sr0.3MnO3/YBa2Cu3O7step-edge-junction structure samples with interfaces of superconducting YBa2Cu3O7(YBCO) and ferromagnetic Pr0.7Sr0.3MnO3(PMSO) layers have been prepared by pulsed laser deposition. The curves of resistivity versus temperature are used to discuss the quality and the interaction of the interfaces between the ferromagnetic PSMO and superconducting YBCO.