Abstract
We have imaged the current noise with atomic resolution in a Josephson scanning tunneling microscope with a Pb-Pb junction. By measuring the current noise as a function of applied bias, we reveal the change from single-electron tunneling above the superconducting gap energy to double-electron charge transfer below the gap energy when Andreev processes become dominant. Our spatially resolved noise maps show that this doubling occurs homogeneously on the surface, and also on impurity locations, demonstrating that indeed the charge pairing is not influenced by disruptions in the superconductor smaller than the superconducting coherence length.
| Original language | English |
|---|---|
| Article number | 104506 |
| Journal | Physical Review B |
| Volume | 100 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 2019 Sept 5 |
Bibliographical note
Funding Information:We acknowledge T. Benschop, Y. M. Blanter, V. Cheianov, T. M. Klapwijk, F. Massee, D. K. Morr, K. van Oosten, M. T. Randeria, and J. M. van Ruitenbeek for valuable discussions. This work was supported by the European Research Council (ERC StG SpinMelt) and by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO/OCW), as part of the Frontiers of Nanoscience program, as well as through a Vidi grant (Grant No. 680-47-536).
Publisher Copyright:
© 2019 authors. Published by the American Physical Society.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics