Frequency-selective single photon detection using a double quantum dot

TL;DR

This paper demonstrates a frequency-tunable on-chip microwave detector using a double quantum dot, capable of detecting single photons by monitoring inelastic electron tunneling induced by photon absorption.

Contribution

The study introduces a novel quantum dot-based microwave detector with tunable frequency and single-photon sensitivity, advancing quantum sensing technology.

Findings

Successful detection of single microwave photons

Frequency tunability via gate voltages

Direct correlation between tunneling events and photon absorption

Abstract

We use a double quantum dot as a frequency-tunable on-chip microwave detector to investigate the radiation from electron shot-noise in a near-by quantum point contact. The device is realized by monitoring the inelastic tunneling of electrons between the quantum dots due to photon absorption. The frequency of the absorbed radiation is set by the energy separation between the dots, which is easily tuned with gate voltages. Using time-resolved charge detection techniques, we can directly relate the detection of a tunneling electron to the absorption of a single photon.