Magnetic Field Dependence of Critical Current in Sm1+xBa2Cu3+yO7−d Coated Conductors Fabricated by Reactive Co-evaporation Method

Abstract

Sm 1+xBa 2Cu 3+yO7−d coated conductors were fabricated by reactive co-evaporation method in the evaporation using drum in dual chambers (EDDC) deposition chamber. The effect of substrate temperature on the superconducting properties was investigated. Three samples were prepared with different substrate temperatures of 740, 780, and 800 °C. In plane and out-of-plane texture were confirmed by X-ray patterns of 2 theta and phi scan and turned out to be almost the same. Angular dependences of critical currents of those samples were measured at 0.5 and 1 T. The magnetic field dependence of critical current with the magnetic field direction parallel to the c-axis of SmBCO film was measured in the range of 0.01–1.5 T. The critical current of the sample prepared at 740 °C was slightly lower than that of other samples in the range of 0.5–1.5 T. Also we investigated the effect of thickness of superconducting layer on the magnetic field dependence. Two samples with different SmBCO film thicknesses of 0.8 and 5 μm were prepared. The magnetic field dependence of critical current in the direction parallel to the c-axis of SmBCO film was measured in the range of 0.01–1.5 T. We found that the normalized critical current of a 5 μm thick sample was higher than that of 0.8 μm thick sample possibly due to the higher pinning force of thick film than that of thin film.