Answers are grounded in this paper and cite their sources.
The temperature variation of the dc critical Josephson current of NbNbOxPb tunnel junctions is investigated experimentally. The experimental data are compared with the temperature dependence of the critical Josephson current derived by Ambegaokar and Baratoff. Deviations giving an evidence of a normal surface layer on niobium are not found.
No takes yet. Share an insight, caveat, or question.
Dettmann et al. (1977) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: