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arXiv · 1308.2208

Quantum nondemolition detection of a propagating microwave photon

Sankar R. Sathyamoorthy·L. Tornberg·Anton F. Kockum·Ben Q. Baragiola·Joshua Combes·C. M. Wilson·Thomas M. Stace·G. Johansson
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Abstract

The ability to nondestructively detect the presence of a single, traveling photon has been a long-standing goal in optics, with applications in quantum information and measurement. Realising such a detector is complicated by the fact that photon-photon interactions are typically very weak. At microwave frequencies, very strong effective photon-photon interactions in a waveguide have recently been demonstrated. Here we show how this type of interaction can be used to realize a quantum nondemolition measurement of a single propagating microwave photon. The scheme we propose uses a chain of solid-state 3-level systems (transmons), cascaded through circulators which suppress photon backscattering. Our theoretical analysis shows that microwave-photon detection with fidelity around 90% can be realized with existing technologies.

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Sankar R. Sathyamoorthy, L. Tornberg, Anton F. Kockum, Ben Q. Baragiola, Joshua Combes, C. M. Wilson, Thomas M. Stace, G. Johansson. 2013-12-19. Quantum nondemolition detection of a propagating microwave photon. https://doi.org/10.1103/physrevlett.112.093601

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