Abstract
The effect of an insulating barrier located at a distance from a NS quantum point contact is analyzed in this work. The Bogoliubov-de Gennes equations are solved for NINS junctions (, anisotropic superconductor; , insulator; and , normal metal), where the NIN region is a quantum wire. For , quasibound states and resonances in the differential conductance are predicted. These resonances depend on the symmetry of the pair potential, the strength of the insulating barrier and . Our results show that in a NINS quantum point contact the number of resonances vary with the symmetry of the order parameter. This is to be contrasted with the results for the NINS junction, in which only the position of the resonances changes with the symmetry.
- Received 12 June 2004
DOI:https://doi.org/10.1103/PhysRevB.71.094515
©2005 American Physical Society