Stranger APCs: Study of Surface Decoration Material for YBCO Films

In this contribution, we report on the study of the vortex pinning properties of YBa 2 Cu 3 O 7-δ (YBCO) film grown on decorated substrate to obtain an improvement of magnetic field dependence of the critical current. Surface-decorated SrTiO 3 (STO) substrates have been obtained by polymer assisted deposition (PAD) with BaZrO3 (BZO) nanoislands uniformly distributed over the substrate surface. Thanks to the high density of the polymer, the viscosity of the solution can be easily adjusted to tune nanoislands' density. Typical values of nanoislands' diameter and height are around 20-50 and 3-5 nm, respectively. YBCO films, derived by metal-organic decomposition (MOD) using low-fluorine precursor solution, were successfully grown on both bare and BZO-decorated STO substrate. Results indicated that surface decoration is effective to enhance pinning at both 77 and 65 K in the whole field range up to 7 T. As a matter of fact, the value of critical current doubled with respect to YBCO film grown on bare STO at 77 K and 1 T.