Chaotic dot-superconductor analog of the Hanbury Brown Twiss effect

TL;DR

This paper investigates positive current correlations in a chaotic quantum dot-superconductor junction, revealing conditions under which these correlations are enhanced or suppressed, thus providing an electrical analog of the optical Hanbury Brown Twiss effect.

Contribution

It introduces a novel electrical analog of the Hanbury Brown Twiss effect using a chaotic quantum dot-superconductor system, analyzing how contact properties influence current correlations.

Findings

Large positive current correlations observed across various contact conditions.

Normal backscattering enhances positive correlations.

Weak magnetic fields suppress the proximity effect while maintaining correlations.

Abstract

As an electrical analog of the optical Hanbury Brown Twiss effect, we study current cross-correlations in a chaotic quantum dot-superconductor junction. One superconducting and two normal reservoirs are connected via point contacts to a chaotic quantum dot. For a wide range of contact widths and transparencies, we find large positive current correlations. The positive correlations are generally enhanced by normal backscattering in the contacts. Moreover, for normal backscattering in the contacts, the positive correlations survive when suppressing the proximity effect in the dot with a weak magnetic field.