Quantum Open-Systems Approach to Current Noise in Resonant Tunnelling Junctions

TL;DR

This paper develops a quantum Markovian master equation to analyze current noise in resonant tunnelling devices, capturing both incoherent and coherent processes, and predicts sub-shot noise statistics in certain regimes.

Contribution

It introduces a novel quantum open-systems approach to current noise, including a method to derive population master equations by adiabatic elimination of coherences.

Findings

Derived a quantum master equation for current noise

Predicted sub-shot noise in strong tunnelling regimes

Provided an alternative to Green's functions methods

Abstract

A quantum Markovian master equation is derived to describe the current noise in resonant tunnelling devices. This equation includes both incoherent and coherent quantum tunnelling processes. We show how to obtain the population master equation by adiabatic elimination of quantum coherences in the presence of elastic scattering. We calculate the noise spectrum for a double well device and predict sub-shot noise statistics for strong tunnelling between the wells. The method is an alternative to Green's functions methods, and population master equations for very small coherently coupled quantum dots.