Quench dynamics of correlated quantum dots

TL;DR

This paper investigates the non-equilibrium relaxation dynamics of a correlated quantum dot system, analyzing how various parameter changes influence current and occupancy, revealing many-body effects and the role of initial correlations.

Contribution

It provides a detailed analysis of the relaxation dynamics of a quantum dot with Coulomb interactions, including effects of parameter changes and bias voltages, connecting to the interacting resonant level model.

Findings

Identification of many-body effects during relaxation

Influence of initial correlations on dynamics

Behavior under different parameter change protocols

Abstract

We study the relaxation dynamics of a quantum dot with local Coulomb correlations coupled to two noninteracting leads which are held in grandcanonical equilibrium. Only charge degrees of freedom are considered and the dot is described by a model which in the scaling limit becomes equivalent to the interacting resonant level model. The time evolution of the current and dot occupancy resulting out of changes of the dot-lead coupling, the dots onsite energy, or the charging energy are studied. Abrupt and smooth parameter changes as well as setups with and without driving bias voltage are considered. For biased dots we investigate the often studied response after turning on the dot-lead coupling but also the experimentally more relevant case in which the voltage is turned on. We identify and explain a variety of interesting many-body effects and clarify the role of initial correlations.