Influence of electronic interferences on the Andreev conductance

✍ Scribed by H. Pothier; S. Guéron; D. Esteve; M.H. Devoret

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 401 KB
• Volume: 203
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(94)90063-9

✦ Synopsis

We have performed an interference experiment with two tunnel junctions between a thin normal metal wire and a superconducting fork. We have found that the subgap current is strongly modulated by the difference between the superconducting phases at the two junctions. Our results agree with the recent prediction that multiple tunnel attempts of electron pairs, which occur when electrons are weakly confined, can add coherently if the pair consists of nearly time-reversed states. The current modulation results from the dephasing between the corresponding tunnel amplitudes at the two junctions. When the normal wire is covered by a second superconductor, the conductance is strongly enhanced.