Quantum Photovoltaic Effect in Double Quantum Dots

TL;DR

This paper investigates how quantum effects in a driven microwave resonator influence photovoltaic current in a double quantum dot system, revealing a double peak frequency dependence due to quantum interactions.

Contribution

It introduces the analysis of quantum electromagnetic effects on photovoltaic current in double quantum dots, highlighting the double peak structure caused by quantum interactions.

Findings

Photovoltaic current exhibits a double peak dependence on microwave frequency.

The peak separation is determined by photon-electron interaction strength.

Increased relaxation processes suppress the quantum double peak structure.

Abstract

We analyze the photovoltaic current through a double quantum dot system coupled to a high-quality driven microwave resonator. The conversion of photons in the resonator to electronic excitations produces a current flow even at zero bias across the leads of the double quantum dot system. We demonstrate that due to the quantum nature of the electromagnetic field in the resonator, the photovoltaic current exhibits a double peak dependence on the frequency $\omega$ of an external microwave source. The distance between the peaks is determined by the strength of interaction between photons in the resonator and electrons in the double quantum dot. The double peak structure disappears as strengths of relaxation processes increases, recovering a simple classical condition for maximal current when the microwave frequency is equal to the resonator frequency.