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arXiv · 2003.04625

A superconducting detector that counts microwave photons up to two

Andrii M. Sokolov·Frank K. Wilhelm
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Abstract

We propose a detector of microwave photons which can distinguish the vacuum state, one-photon state, and the states with two or more photons. Its operation is based on the two-photon transition in a biased Josephson junction and detection occurs when it switches from a superconducting to a normal state. We model the detector theoretically. The detector performs with more than 90% success probability in several microseconds. It is sensitive for the 8.2GHz photons. The working frequency could be set at the design stage in the range from about 1GHz to 20GHz.

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Andrii M. Sokolov, Frank K. Wilhelm. 2020-03-10. A superconducting detector that counts microwave photons up to two. https://doi.org/10.1103/physrevapplied.14.064063

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