Real-time renormalization group and charge fluctuations in quantum dots

TL;DR

This paper introduces a real-time perturbative renormalization-group method to analyze nonequilibrium quantum dot systems, accurately capturing conductance behavior in regimes with energy broadening and dissipation.

Contribution

It presents a novel cutoff-independent formalism for real-time renormalization group analysis of quantum systems coupled to environments, including energy broadening and dissipation effects.

Findings

Reliable nonlinear conductance results in the Anderson impurity model

Quantitative analysis of mixed-valence and empty-orbital regimes

Formalism applicable to nonequilibrium quantum systems

Abstract

We develop a perturbative renormalization-group method in real time to describe nonequilibrium properties of discrete quantum systems coupled linearly to an environment. We include energy broadening and dissipation and develop a cutoff-independent formalism. We present quantitatively reliable results for the nonlinear conductance in the mixed-valence and empty-orbital regime of the nonequilibrium Anderson impurity model with finite on-site Coulomb repulsion.