Scanning Tunneling Spectroscopy Study of the Proximity Effect in a Disordered Two-Dimensional Metal
Abstract
The proximity effect between a superconductor and a highly diffusive two-dimensional metal is revealed in a scanning tunneling spectroscopy experiment. The in situ elaborated samples consist of superconducting single crystalline Pb islands interconnected by a nonsuperconducting atomically thin disordered Pb wetting layer. In the vicinity of each superconducting island the wetting layer acquires specific tunneling characteristics which reflect the interplay between the proximity-induced superconductivity and the inherent electron correlations of this ultimate diffusive two-dimensional metal. The observed spatial evolution of the tunneling spectra is accounted for theoretically by combining the Usadel equations with the theory of dynamical Coulomb blockade; the relevant length and energy scales are extracted and found in agreement with available experimental data.
- Publication:
-
Physical Review Letters
- Pub Date:
- April 2013
- DOI:
- 10.1103/PhysRevLett.110.157003
- arXiv:
- arXiv:1401.8102
- Bibcode:
- 2013PhRvL.110o7003S
- Keywords:
-
- 74.45.+c;
- 74.55.+v;
- 74.78.Na;
- Proximity effects;
- Andreev effect;
- SN and SNS junctions;
- Mesoscopic and nanoscale systems;
- Condensed Matter - Superconductivity;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 5 pages, 3 figures, supporting information available in the journal web site or upon request