Thin film nanocomposites based on YBCO with defects comprised of self-assembled inclusions

Abstract

The critical current of YBCO superconducting coatings in external magnetic field can be enhanced by incorporating high density of extended nanometer-sized defects to act as pinning centers for magnetic vortexes. One particular variant involves the deposition superconducting film with columnar defects comprised of self-assembled BaZrO3, BaSnO3 or BaHfO3 nanoinclusions. Here we report the results of our study of YBCO films with different inclusions prepared by MOCVD. For the first time, we succeeded in growth of YBCO films with oriented nanoinclusions of BaCeO3 phase and demonstrate that it does not reduce Tc of YBCO, in contrast to BaZrO3 or BaSnO3. The best composite thin films revealed the Tc value of about 88K and critical current density at 77K above 1MA/cm2 in self-field and around 0.3 MA/cm2 in 1 T (B//c). © 2010 IOP Publishing Ltd.