2001/03/23 by M. Titov, N. A. Mortensen, N. Asger Mortensen +3
Physics and Astronomy · #Laser-Matter Interactions and Applications #Quantum Mechanics and Applications #Quantum chaos and dynamical systems #cond-mat.dis-nn #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.64.134206
published as Phys. Rev. B 64, 134206 (2001) · 12 pages, 5 figures
arxiv created 2001/03/23 · openalex publication_date 2001/09/11 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
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.