2026-04-06 スイス連邦工科大学ローザンヌ校（EPFL）
＜関連情報＞
- https://actu.epfl.ch/news/a-tiny-detector-for-microwave-photons-could-advanc/
- https://www.science.org/doi/10.1126/sciadv.aeb9784
超伝導高インピーダンス共振器に結合された二重量子ドットに基づく、波長可変高効率マイクロ波光子検出器 Tunable high-efficiency microwave photon detector based on a double quantum dot coupled to a superconducting high-impedance cavity
Fabian Oppliger, Wonjin Jang, Aldo Tarascio, Franco De Palma, […] , and Pasquale Scarlino
Science Advances Published:3 Apr 2026
DOI:https://doi.org/10.1126/sciadv.aeb9784
Abstract
High-efficiency single-photon detection in the microwave domain is a key enabling technology for various quantum applications. However, the extremely low energy of microwave photons presents a fundamental challenge, preventing direct photon-to-charge conversion as achieved in optical systems using semiconductors. Here, we demonstrate continuous microwave photon detection with an efficiency approaching 70% in the single-photon regime. We use a hybrid system comprising a gate-defined double quantum dot (DQD) charge qubit in a gallium arsenide/aluminum gallium arsenide heterostructure, coupled to a high-impedance Josephson junction array cavity. We systematically optimize the hybrid architecture to maximize the detection efficiency by leveraging strong charge-photon coupling, tunable DQD tunnel rates, and the frequency tunability of both subsystems. The system efficiency is characterized over a frequency range of 3 to 5.2 gigahertz. Our results establish semiconductor-based cavity–quantum electrodynamics architectures as a scalable and versatile platform for efficient microwave photon detection, opening promising avenues for quantum microwave optics and quantum information technologies.
