Weak link between conventional and unconventional superconductors

✍ Scribed by Sungkit Yip

• Publisher: Springer US
• Year: 1993
• Tongue: English
• Weight: 650 KB
• Volume: 91
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00120849

✦ Synopsis

In this paper we consider the Josephson coupling between a conventional and an unconventional superconductor through a constriction. It is demonstrated that a weak link is very different from a tunnel junction. In particular, in an orientation where the coupling in a tunnel junction vanishes because of symmetry, the Josephson current in the case of a weak link can nevertheless be finite, albeit with the distinctive characteristics of(i) a current phase relationship with a period of 27r/n, (ii) the critical current near but below the transition temperature T 1 of the lower transition temperature superconductor is proportional to (1 -(T/T1) ) n/:, where n is an integer determined by the symmetry.

*It is probably true that an example of this was first pointed out by Ambegaokar, deGennes and Rainer 7 in the context of 3He-A.