Proximity-induced transport in hybrid mesoscopic normal-superconducting metal structures

TL;DR

This paper presents a theoretical analysis of transport phenomena in mesoscopic superconductor/normal-metal structures, focusing on conductance anomalies, temperature effects, and Josephson effects using quasiclassical Green's functions.

Contribution

It introduces a comprehensive theoretical framework for understanding proximity-induced transport and Josephson effects in mesoscopic S/N structures, including new insights into conductance anomalies and critical current behavior.

Findings

Identification of zero bias and finite bias conductance anomalies.

Discovery of a second maximum in conductance near T_c.

Analysis of sign reversal in Josephson critical current.

Abstract

Using an approach based on quasiclassical Green's functions we present a theoretical study of transport in mesoscopic S/N structures in the diffusive limit. The subgap conductance in S/N structures with barriers (zero bias and finite bias anomalies) are discused. We also analyse the temperature dependence of the conductance variation $\delta S(T)$ for a Andreev interferometer. We show that besides the well know low temperature maximum a second maximum near $T_c$ may appear. We present the results of studies on the Josephson effect in 4 terminal S/N/S contacts and on the possible sign reversal of the Josephson critical current.