Unusually clear phonon structure from superconducting Nb is observed in tunneling into the normal side of ultrathin AlNb (NS) proximity sandwiches. Contrary to recent reports, this phonon structure is not inverted. The possible utility of such spectra in deducing the properties of the superconducting state in the underlying S electrode is pointed out.
ASJC Scopus subject areas
- Physics and Astronomy(all)