Abstract
The grain boundaries (GB's) in the intermetallic superconductor MgB 2 , interestingly, do not show suppression of supercurrent density. This unexpected behavior has been investigated by a scanning tunneling microscopy/spectroscopy technique at atomic resolution. The GB in MgB 2 is seen as an amorphous region extending from ∼50 to 200 A and has a metallic character. This observation supports proximity coupling between the grains, which explains why supercurrent density does not degrade in this material. The results for another intermetallic superconductor YNi 2 B 2 C having GB's (average width ∼30 A) that are quasi-insulating in nature have also been presented and compared with the former.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
