Effect of the shot-noise on a Coulomb blockaded single Josephson junction

TL;DR

This paper explores how shot noise affects Coulomb blockade in a mesoscopic Josephson junction, extending phase correlation theory to non-Gaussian noise and demonstrating potential for noise detection.

Contribution

It introduces a theoretical extension for non-Gaussian noise effects on Coulomb blockade and experimentally confirms asymmetry-induced conductance shifts and ratchet effects.

Findings

Asymmetry causes conductance minimum shift from zero voltage.

Nonzero current at zero voltage observed due to ratchet effect.

High-impedance junctions can serve as noise detectors.

Abstract

We have investigated how the Coulomb blockade of a mesoscopic Josephson junction in a high-impedance environment is suppressed by shot noise from an adjacent junction. The presented theoretical analysis is an extension of the phase correlation theory for the case of a non-Gaussian noise. Asymmetry of the non-Gaussian noise should result in the shift of the conductance minimum from zero voltage and the ratchet effect (nonzero current at zero voltage), which have been experimentally observed. The analysis demonstrates that a Coulomb blockaded tunnel junction in a high impedance environment can be used as an effective noise detector.