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arXiv · 1011.4329

Microwave Photon Counter Based on Josephson Junctions

Y. -F. Chen·D. Hover·S. Sendelbach·L. Maurer·S. T. Merkel·E. J. Pritchett·F. K. Wilhelm·R. McDermott
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Abstract

We describe a microwave photon counter based on the current-biased Josephson junction. The junction is tuned to absorb single microwave photons from the incident field, after which it tunnels into a classically observable voltage state. Using two such detectors, we have performed a microwave version of the Hanbury Brown and Twiss experiment at 4 GHz and demonstrated a clear signature of photon bunching for a thermal source. The design is readily scalable to tens of parallelized junctions, a configuration that would allow number-resolved counting of microwave photons.

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Y. -F. Chen, D. Hover, S. Sendelbach, L. Maurer, S. T. Merkel, E. J. Pritchett, F. K. Wilhelm, R. McDermott. 2010-11-19. Microwave Photon Counter Based on Josephson Junctions. https://doi.org/10.1103/physrevlett.107.217401

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