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arXiv · 1003.4654

Operating quantum waveguide circuits with superconducting single-photon detectors

C. M. Natarajan·A. Peruzzo·S. Miki·M. Sasaki·Z. Wang·B. Baek·S. Nam·R. H. Hadfield·J. L. O'Brien
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Abstract

Advanced quantum information science and technology (QIST) applications place exacting de- mands on optical components. Quantum waveguide circuits offer a route to scalable QIST on a chip. Superconducting single-photon detectors (SSPDs) provide infrared single-photon sensitivity combined with low dark counts and picosecond timing resolution. In this study we bring these two technologies together. Using SSPDs we observe a two-photon interference visibility of 92.3\pm1.0% in a silica-on-silicon waveguide directional coupler at \lamda = 804 nm-higher than that measured with silicon detectors (89.9\pm0.3%). We further operated controlled-NOT gate and quantum metrology circuits with SSPDs. These demonstrations present a clear path to telecom-wavelength quantum waveguide circuits.

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C. M. Natarajan, A. Peruzzo, S. Miki, M. Sasaki, Z. Wang, B. Baek, S. Nam, R. H. Hadfield, J. L. O'Brien. 2010-03-24. Operating quantum waveguide circuits with superconducting single-photon detectors. https://doi.org/10.1063/1.3413948

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