Characterization of Anomalous Pair Currents in Josephson Junction Networks

TL;DR

This paper investigates anomalous large currents in superconductive Josephson junction networks, attributing them to Cooper pair hopping and inhomogeneous pair distribution, supported by experimental measurements and a theoretical model.

Contribution

It introduces a theoretical model explaining anomalous currents in Josephson networks as resulting from inhomogeneous Cooper pair distribution.

Findings

Large anomalous currents observed in specific network branches

Temperature dependence indicates Cooper pair hopping as the cause

Theoretical model predicts inhomogeneous Cooper pair distribution

Abstract

Measurements performed on superconductive networks shaped in the form of planar graphs display anomalously large currents when specific branches are biased. The temperature dependencies of these currents evidence that their origin is due to Cooper pair hopping through the Josephson junctions connecting the superconductive islands of the array. The experimental data are discussed in terms of a theoretical model which predicts, for the system under consideration, an inhomogeneous Cooper pair distribution on the superconductive islands of the network.