Charge and energy transfer in ac-driven Coulomb-coupled double quantum dots

TL;DR

This paper investigates charge and energy transfer in a Coulomb-coupled double quantum dot system under periodic driving, revealing significant energy exchange and the effects of strong correlations on transport properties.

Contribution

It introduces a mean-field slave-spin 1 approach to analyze energy and charge dynamics in strongly correlated double quantum dots with time-dependent driving.

Findings

Up to 43% of energy injected can transfer to the undriven dot.

Currents in the undriven dot are comparable to those in the driven dot.

Coulomb interactions significantly affect the resistance of the driven quantum dot.

Abstract

We study the dynamics of charge and energy currents in a Coulomb-coupled double quantum dot system, when only one of the two dots is adiabatically driven by a time-periodic gate that modulates its energy level. Although the Coulomb coupling does not allow for electron transfer between the dots, it enables an exchange of energy between them which induces a time variation of charge in the undriven dot. We describe the effect of electron interactions at low temperature using a time-dependent slave-spin 1 formulation within mean-field that efficiently captures the main effects of the strong correlations as well as the dynamical nature of the driving. We find that the currents induced in the undriven dot due to the mutual friction between inter-dot electrons are same order than those generated in the adiabatically driven dot. Interestingly, up to 43$\%$ percent of the energy injected by the ac sources can be transferred from the driven dot to the undriven one. We complete our analysis by studying the impact of the Coulomb interaction on the resistance of the quantum dot that is driven by the gate.