This title appears in the Scientific Report : 2014 

Crossover from Josephson Effect to Single Interface Andreev Reflection in Asymmetric Superconductor/Nanowire Junctions
Günel, H. Y. (Corresponding Author)
Borgwardt, N. / Batov, I. E. / Hardtdegen, Hilde / Sladek, Kamil / Panaitov, Gregory / Grützmacher, Detlev / Schäpers, Thomas
JARA-FIT; JARA-FIT
Halbleiter-Nanoelektronik; PGI-9
Nano letters, 14 (2014) S. 4977-4981
Washington, DC ACS Publ. 2014
25118624
10.1021/nl501350v
Journal Article
Frontiers of charge based Electronics
Please use the identifier: http://dx.doi.org/10.1021/nl501350v in citations.
We report on the fabrication and characterization of symmetric nanowire-based Josephson junctions, that is, Al- and Nb-based junctions, and asymmetric junctions employing superconducting Al and Nb. In the symmetric junctions, a clear and pronounced Josephson supercurrent is observed. These samples also show clear signatures of subharmonic gap structures. At zero magnetic field, a Josephson coupling is found for theasymmetric Al/InAs-nanowire/Nb junctions as well. By applying a magnetic field above the criticalfield of Al or by raising the temperature above the critical temperature of Al the junction can be switched to an effective singleinterface superconductor/nanowire structure. In this regime, a pronounced zero-bias conductance peak due to reflectionless tunneling has been observed.