Monodisperse BaZrO₃ nanocrystals and flux pinning effect on upscaling MOD-derived (Y,Dy)Ba₂Cu₃O_{7− δ} superconducting tapes

Abstract

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