Experimental Examination on E-J characteristics in Superconducting PbBi Alloys

The electric field E vs. current density J in two superconducting PbBi samples with quite different J c were measured at various magnetic fields and temperatures by using a usual resistive method. A nonlinear E-J characteristic similar to that in high T c superconductors was observed. Each E-J curve collapsed onto one of the two universal branches and a scaling behavior was recognized. It turned out that the flux pinning characteristic influences E-J curve and the scaling significantly. The stronger flux pinning makes T g or B g higher.