Monodisperse BaZrO3 nanocrystals and flux pinning effect on upscaling MOD-derived (Y,Dy)Ba2Cu3O7− δ superconducting tapes

Abstract

In the present work, monodisperse BaZrO3 (BZO) nanocrystals with controllable sizes are successfully introduced into trifluoroacetate metal–organic deposition derived (Y,Dy)Ba2Cu3O7−δ ((Y,Dy)BCO)-coated superconducting tapes to act as effective pinning centers. The BZO nanocrystal addition strategy is extended to upscaling coated conductors as long as hundreds of meters, and as thick as 3.4 μm, of (Y,Dy)BCO layers. The corresponding superconducting performances of BZO-added (Y,Dy)BCO-coated conductors are systematically investigated under various applied magnetic fields and temperatures. It is revealed that the I c (77 K, self-field) of BZO-added tapes decreases linearly with BZO concentration, while the corresponding in-field lift-factors increase for all studied BZO additions. In-field J c values under various fields at low temperatures show that the (Y,Dy)BCO tape with 5%-BZO addition exhibits a better performance than that of other concentrations. Besides, this benefit of BZO addition appears identical for both thin and thick samples, as well as for tapes that are hundreds of meters long. The angular dependence of in-field I c also shows that significant improvement occurs in all the studied angular ranges after nanocrystal BZO additions, demonstrating that the nanocrystal addition strategy is of great value for upscaling commercial (Y,Dy)BCO tape for in-field applications.