Dependence of critical current density with cross section of sample in ceramic superconductors YBa2CU3O7δ and Bi1.6PB0.4Sr2Ca2CU3Oy

Critical current density (Jc) is one of the important parameters of superconductors. It depends on many factors, for example, the cross section of sample. Ceramic superconductors YBa2CU3O7δ and Bi1.6PB0.4Sr2Ca2CU3Oy were chosen to investigate how the Jc is depend on cross section. Rectangular samples with different cross sections were fabricated with the same synthesis conditions by the solid state reaction method. The results of XRD show that the dominant phase in YBa2CU3O7δ and Bi1.6PB0.4Sr2Ca2CU3Oy are 123 and 2223 respectively. The results of Jc measurements show that is both superconductors, the Jc decreases with increasing of cross section (A). The type of dissipation obeys a power law with relation Jc=αA-β