Quantum noise theory for quantum transport through nanostructures

TL;DR

This paper introduces a quantum noise approach to analyze quantum transport in nanostructures, providing exact calculations of current and noise even with interactions like Coulomb blockade.

Contribution

It develops a quantum noise framework for quantum transport, linking reservoir fluctuations to system dynamics, and applies it to quantum dots with exact results.

Findings

Exact calculation of current and noise in quantum dots

Quantum noise approach handles Coulomb interactions

Application to single quantum dot transport

Abstract

We develop a quantum noise approach to study quantum transport through nanostructures. The nanostructures, such as quantum dots, are regarded as artificial atoms, subject to quasi-equilibrium fermionic reservoirs of electrons in biased leads. Noise operators characterizing the quantum fluctuation in the reservoirs are related to the damping and fluctuation of the artificial atoms through the quantum Langevin equation. The average current and current noise are derived in terms of the reservoir noise correlations. In the white-noise limit, we show that the current and current noise can be exactly calculated by the quantum noise approach, even in the presence of interaction such as Coulomb blockade. As a typical application, the average current and current noise through a single quantum dot are studied.