Nanosize texture and transport properties in Y-Ba-Cu-O films

The magnetic-transport properties of thin YBCO films are accounted for by a network of intergranular “hidden” Josephson junctions. An accurate X-ray analysis reveals the existence of structural patterns with the same distribution function as the one found by fitting the Jc vs. B curves. The correspondence between the two distributions enables us to establish that the transport mechanism in those films is driven by the nanosize structural pattern behaving as an intergranular “hidden” array of Josephson junctions. It allows to find out for the first time how the Jc vs. B curves scale with temperature. The full analysis enables to determine the main parameters to modify in order to exploit the intrinsic properties of this network towards applications.