Current Carrying Properties in High Tc Y-Ba-Cu-O System

Abstract

The transition temperature, Tc, and the critical current density, Jc(B), at 4.2 K have been studied in high Tc Y-Ba-Cu oxide system. A very large anisotropy, very fast degradations at low fields, and a large hysteresis in Jc(B) have been observed in this system. The cause of the large anisotropy might be the strong c-axis orientation parallel to the direction of the pressing and the low dimensionality of the crystal structure of this material. Although Jc value is very small, the decrease in Jc with increasing magnetic field from 2 to 27 T is estimated to amount to only about 20 %, which shows a high potential for practical use at high fields when Jc is raised by the introduction of strong pinning centers in the Y-Ba-Cu oxide system.