Properties of Nb/InAs/Nb hybrid step junctions

Experimental results for novel superconductor/semiconductor hybrid systems are presented. The junctions have a step-like geometry, employing two Nb electrodes which are evaporated onto a step that is etched in InAs. Such a geometry allows one to fabricate short weak links (approximately 200nm) as we...

Full description

Saved in:
Bibliographic Details
Published in:Journal of low temperature physics 1997, Vol.106 (3-4), p.321-326
Main Authors: Lachenmann, S G, Kastalsky, A, Friedrich, I, Foerster, A, Uhlisch, D
Format: Article
Language:English
Subjects:
Current voltage characteristics
Electric currents
Electrochemical electrodes
Etching
Niobium
Semiconducting indium compounds
Semiconductor growth
Semiconductor materials
Superconducting materials
Thin films
Transport properties
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Experimental results for novel superconductor/semiconductor hybrid systems are presented. The junctions have a step-like geometry, employing two Nb electrodes which are evaporated onto a step that is etched in InAs. Such a geometry allows one to fabricate short weak links (approximately 200nm) as well as to realize a variety of heterostructure potential profiles along the channel between the superconducting electrodes, since this channel is oriented parallel to the growth direction of the heterostructure. Different semiconductor heterostructures, such as low p-doped InAs, whose native surface inversion layer has the character of a two-dimensional electron gas (2DEG), or npn-InAs heterostructures, where the 2DEG of a thin (150nm) p-layer is sandwiched between two n-InAs layers, are used. By measuring the current-voltage characteristics at 4.2K, supercurrents, subharmonic gap structures, as well as excess currents, are observed.
ISSN:0022-2291
1573-7357
DOI:10.1007/BF02399633