Characterization of a microwave frequency resonator via a nearby quantum dot

TL;DR

This paper investigates a hybrid system combining a microwave resonator and a quantum dot, demonstrating how the quantum dot can be used to measure the resonator's transmission spectrum through conductance changes.

Contribution

It introduces a method to characterize a microwave resonator via a nearby quantum dot, revealing interaction effects and enabling spectrum measurement using the quantum dot.

Findings

Microwave field reduces quantum dot conductance due to electron heating.

Resonator transmission spectrum can be measured through quantum dot conductance.

Interaction effects enable quantum dot-based resonator characterization.

Abstract

We present measurements of a hybrid system consisting of a microwave transmission-line resonator and a lateral quantum dot defined on a GaAs heterostructure. The two subsystems are separately characterized and their interaction is studied by monitoring the electrical conductance through the quantum dot. The presence of a strong microwave field in the resonator is found to reduce the resonant conductance through the quantum dot, and is attributed to electron heating and modulation of the dot potential. We use this interaction to demonstrate a measurement of the resonator transmission spectrum using the quantum dot.