Shot Noise in Mesoscopic Systems with Resonance Andreev Tunneling

TL;DR

This paper develops a scattering-matrix formalism to analyze shot noise in quantum NS contacts with Andreev resonances, revealing features that allow phase determination of Andreev reflections.

Contribution

It introduces a new formalism for shot noise analysis in mesoscopic systems with smeared Andreev levels, highlighting how noise features relate to Andreev resonance phases.

Findings

Noise spectral density exhibits characteristic features due to Andreev resonances.

Analysis of singularities in noise can determine phases of Andreev reflection amplitudes.

Formalism applies to single-channel quantum NS contacts with smeared Andreev levels.

Abstract

The general scattering-matrix formalism is suggested for the description of shot noise in single-channel quantum NS contacts in the presence of smeared Andreev levels in the $eV<\Delta$ regime. It is shown that the noise spectral density as a function of frequency shows a number of characteristic features due to the presence of the Andreev resonances in the system. It turns out that, by analyzing these singularities, one can determine the relative phases of the Andreev reflection amplitudes corresponding to the neighboring resonances.