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Superconducting Proximity Effect and Universal Conductance Fluctuations

Tero T. Heikkila·Martti M. Salomaa·C. J. Lambert
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Abstract

We examine universal conductance fluctuations (UCFs) in mesoscopic normal-superconducting-normal (N-S-N) structures using a numerical solution of the Bogoliubov - de Gennes equation. We discuss two cases depending on the presence (``open'' structure) or absence (``closed'' structure) of quasiparticle transmission. In contrast to N-S structures, where the onset of superconductivity increases fluctuations, we find that UCFs are suppressed by superconductivity for N-S-N structures. We demonstrate that the fluctuations in ``open'' and ``closed'' structures exhibit distinct responses to an applied magnetic field and to an imposed phase variation of the superconducting order parameter.

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Tero T. Heikkila, Martti M. Salomaa, C. J. Lambert. 1999-08-02. Superconducting Proximity Effect and Universal Conductance Fluctuations. https://doi.org/10.1103/physrevb.60.9291

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