Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Andreev levels in a single-channel conductor.
AU - Titov, M.
AU - Mortensen, N. A.
AU - Schomerus, H.
AU - Beenakker, C. W. J.
PY - 2001
Y1 - 2001
N2 - 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.
AB - 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.
M3 - Journal article
VL - 64
SP - 134206
JO - Physical review B
JF - Physical review B
SN - 1550-235X
ER -