Effect of grain network modifications due to additives on critical current (Ic) in Bi-2212 superconductor

TLDR: In this paper, the effect of additives (Ag, Ag2O and BaBiO3) on the weak link behavior of Bi-2212 in bulk form was investigated and it was observed that the addition of silver (Ag) metal powder improves the connectivity between the grains by proximity effect and thereby enhances the current carrying capability at temperatures very close to Tc De Gennes and Clarke models.

Abstract: The presence of weak links in high-Tc superconductors is a major drawback in achieving high critical current densities The present study deals with the effect of additives (Ag, Ag2O and BaBiO3) on the weak link behaviour of Bi-2212 in bulk form It is observed that the addition of silver (Ag) metal powder improves the connectivity between the grains by proximity-effect and thereby enhances the current carrying capability at temperatures very close to Tc De Gennes and Clarke models have been invoked to establish that Bi-2212 containing insulating additives (BaBiO3 and Ag2O) show a superconductor–insulator–superconductor (S–I–S) type grain network and thereby enhance the weak link behaviour, whereas metallic Ag addition shows a superconductor–normal metal–superconductor (S–N–S) behaviour and is, therefore, a potential candidate for large scale applications Further support to this data is obtained from ac susceptibility studies carried out at different magnetic field strengths (01–40 Oe)