Journal article ยท Preprint article
Andreev levels in a single-channel conductor
We calculate the subgap density of states of a disordered single-channel normal metal connected to a superconductor at one end (normal-metal-superconductor junction) or at both ends [superconductor-normal-metal-superconductor (SNS) junction]. The probability distribution of the energy of a bound state (Andreev level) is broadened by disorder.
In the SNS case the twofold degeneracy of the Andreev levels is removed by disorder leading to a splitting in addition to the broadening. The distribution of the splitting is given precisely by Wigner's surmise from random-matrix theory. For strong disorder the mean density of states is largely unaffected by the proximity to the superconductor, because of localization, except in a narrow energy region near the Fermi level, where the density of states is suppressed with a log-normal tail.
Language: | English |
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Publisher: | American Physical Society (APS) |
Year: | 2001 |
Pages: | 12 |
ISSN: | 10953795 , 01631829 , 1550235x , 10980121 and 24699950 |
Types: | Journal article and Preprint article |
DOI: | 10.1103/PhysRevB.64.134206 |
ORCIDs: | Mortensen, Asger |