Effect of the In-Plane Epitaxial Mismatch between the Substrate and the Film on the Properties of YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ Films

We study the effect of the in-plane epitaxial mismatch between the substrate and the film on the crystallographic structure and the transport properties of YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ superconducting films of thicknesses ranging between 600 and 3000Å. The films are grown by pulsed laser deposition on the new type of single-crystalline substrates prepared by Czochralski method, with the chemical formula (SrAl$\text{}_{0.5}$Ta$\text{}_{0.5}$O$\text{}_{3}$)$\text{}_{0.7}$(CaAl$\text{}_{0.5}$Ta$\text{}_{0.5}$O$\text{}_{3}$)$\text{}_{0 .1}$(LaAlO$\text{}_{3}$)$\text{}_{0.2}$. We find that superconducting properties of the samples are excellent, and generally they improve with increasing of the film thickness as a result of improved structural ordering. We also investigate the influence of the film thickness on the behavior of the critical current densities.