Mesoscopic Conductance Oscillations in a Normal Sample Controlled by the Superconductivity of an NS Boundary

TL;DR

This paper investigates how the conductance of a mesoscopic normal metal sample is influenced by both magnetic flux and supercurrent in an SNS Josephson junction, revealing conductance oscillations linked to these effects.

Contribution

It introduces a model showing conductance oscillations in a mesoscopic normal metal controlled by supercurrent and magnetic flux, highlighting the role of Josephson current in conductance behavior.

Findings

Conductance oscillations depend on magnetic flux and supercurrent.

The model demonstrates a link between Josephson current and conductance.

Measurement of thermal noise can directly observe the Josephson current.

Abstract

An arrangement of mesoscopic experiments is considered when the conductance of a mesoscopic normal metal sample is governed not only by the magnetic flux threading the sample but by the supercurrent inside the superconductor coupled to the normal metal sample as well. The conductance of the system is shown to be associated with the SNS Josephson current $j_J$ through the normal part of the system. By way of example we consider a model when quasi1D wire is connected to a superconductor by its ends and coupled to two reservoirs of electrons by the normal metallic leads. The conductance oscillations caused by change of magnetic field and the supercurrent inside the superconductor have been calculated. The possibility of direct observation of the Josephson current through measurement of the thermal noise in the normal conductor is suggested.