In-Field J_c Properties in the Longitudinal Magnetic Field of BaHfO₃-Doped-Multilayered SmBa₂Cu₃O_y Films on Metal Tapes for the Cable Application

Abstract

In the longitudinal magnetic field state, critical current density (J_c) of a superconductor enhances compared with the J_c in self-field and it is called as J_c gain. We have reported J_c gain in BaHfO₃-doped-multilayered (ML) SmBa₂Cu₃O_y(Sm123) films on oxide single crystalline substrates. In this study, we aim for the J_c gain appearance in ML-Sm123 films on IBAD-MgO metal tapes for power cable application. We observed the J_c gain on metal tapes with good reproducibility. From viewpoints of the flux pinning and super-current flow, important factors for the J_c gain at 77 K were higher interface density, self-organized BHO nanorods with larger diameter, and the reduction of a ML-structure disturbances.

Fig. 1 Normalized J_c-B curves of Sm123 films at 77 K in B//ab，B//I (longitudinal magnetic field state).