EFFECTS OF Gd DOPING IN YBa2Cu3O7-delta ON THE CRITICAL CURRENT DENSITY

Abstract

Gd is successfully embedded into YBa 2 Cu 3 O 7-δ by the solid state reaction. Rietveld refinements show that Gd replaces Cu in the unit cell. By magnetization and resistivity measurements, the effects of Gd -doping in YBCO on the critical current density J c and the critical temperature T c in YBa 2 Cu 3 O 7-δ( YBCO ) have been investigated. J c varies with the applied field and the content of Gd and has a maximum at x = 0.03. The characteristic behavior of J c with varying the Gd content can be explained in terms of the competition between two different effects caused by Gd -doping in YBCO: the inhomogeneity of grains distribution in nano-scale and the variation of superconductivity.