Universal gap fluctuations in the superconductor proximity effect

M. G. Vavilov; P. W. Brouwer; V. Ambegaokar; C. W. J. Beenakker

doi:10.1103/physrevlett.86.874

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Universal gap fluctuations in the superconductor proximity effect

M. G. Vavilov·P. W. Brouwer·V. Ambegaokar·C. W. J. Beenakker

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Abstract

Random-matrix theory is used to study the mesoscopic fluctuations of the excitation gap in a metal grain or quantum dot induced by the proximity to a superconductor. We propose that the probability distribution of the gap is a universal function in rescaled units. Our analytical prediction for the gap distribution agrees well with exact diagonalization of a model Hamiltonian.

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M. G. Vavilov, P. W. Brouwer, V. Ambegaokar, C. W. J. Beenakker. 2000-06-23. Universal gap fluctuations in the superconductor proximity effect. https://doi.org/10.1103/physrevlett.86.874

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