Suppression of the "quasiclassical" proximity gap in correlated-metal--superconductor structures

Branislav K. Nikolic; J. K. Freericks; P. Miller

doi:10.1103/physrevlett.88.077002

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Suppression of the "quasiclassical" proximity gap in correlated-metal--superconductor structures

Branislav K. Nikolic·J. K. Freericks·P. Miller

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Abstract

We study the energy and spatial dependence of the local density of states in a superconductor--correlated-metal--superconductor Josephson junction, where the correlated metal is a non-Fermi liquid (described by the Falicov-Kimball model). Many-body correlations are treated with dynamical mean-field theory, extended to inhomogeneous systems. While quasiclassical theories predict a minigap in the spectrum of a disordered Fermi liquid which is proximity-coupled within a mesoscopic junction, we find that increasing electron correlations destroy any minigap that might be opened in the absence of many-body correlations.

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Branislav K. Nikolic, J. K. Freericks, P. Miller. 2001-11-23. Suppression of the "quasiclassical" proximity gap in correlated-metal--superconductor structures. https://doi.org/10.1103/physrevlett.88.077002

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