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arXiv · 1501.03881

Theory of microwave single-photon detection using an impedance-matched $Λ$ system

Kazuki Koshino·Kunihiro Inomata·Zhirong Lin·Yasunobu Nakamura·Tsuyoshi Yamamoto
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Abstract

By properly driving a qubit-resonator system in the strong dispersive regime, we implement an "impedance-matched" $Λ$ system in the dressed states, where a resonant single photon deterministically induces a Raman transition and excites the qubit. Combining this effect and a fast dispersive readout of the qubit, we realize a detector of itinerant microwave photons. We theoretically analyze the single-photon response of the $Λ$ system and evaluate its performance as a detector. We achieve a high detection efficiency close to unity without relying on precise temporal control of the input pulse shape and under a conservative estimate of the system parameters. The detector can also be reset quickly by applying microwave pulses, which allows a short dead time and a high repetition rate.

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Kazuki Koshino, Kunihiro Inomata, Zhirong Lin, Yasunobu Nakamura, Tsuyoshi Yamamoto. 2015-01-16. Theory of microwave single-photon detection using an impedance-matched $Λ$ system. https://doi.org/10.1103/physreva.91.043805

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