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arXiv · 2501.07354

Enhancing the sensitivity of single microwave photon detection with bandwidth tunability

Louis Pallegoix·Jaime Travesedo·Alexandre S. May·Léo Balembois·Denis Vion·Patrice Bertet·Emmanuel Flurin
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Abstract

We report on the characteristics of a microwave photon counter device based on a superconducting transmon qubit. Its design is similar to [arXiv:2307.03614], with an additional bandwidth tuning circuit that allows optimizing the device efficiency and noise. Owing to this new feature and to improvements in device fabrication, a power sensitivity of $3 \cdot 10^{-23} \mathrm{W}/\sqrt{\mathrm{Hz}}$ is reached. We confirm the high performance of the device by measuring single spin microwave fluorescence.

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Louis Pallegoix, Jaime Travesedo, Alexandre S. May, Léo Balembois, Denis Vion, Patrice Bertet, Emmanuel Flurin. 2025-01-13. Enhancing the sensitivity of single microwave photon detection with bandwidth tunability. https://doi.org/10.1103/dbqj-qld5

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