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arXiv · 1402.2210

Room temperature single-photon detectors for high bit rate quantum key distribution

L. C. Comandar·B. Fröhlich·M. Lucamarini·K. A. Patel·A. W. Sharpe·J. F. Dynes·Z. L. Yuan·R. V. Penty·A. J. Shields
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Abstract

We report room temperature operation of telecom wavelength single-photon detectors for high bit rate quantum key distribution (QKD). Room temperature operation is achieved using InGaAs avalanche photodiodes integrated with electronics based on the self-differencing technique that increases avalanche discrimination sensitivity. Despite using room temperature detectors, we demonstrate QKD with record secure bit rates over a range of fiber lengths (e.g. 1.26 Mbit/s over 50 km). Furthermore, our results indicate that operating the detectors at room temperature increases the secure bit rate for short distances.

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L. C. Comandar, B. Fröhlich, M. Lucamarini, K. A. Patel, A. W. Sharpe, J. F. Dynes, Z. L. Yuan, R. V. Penty, A. J. Shields. 2014-02-10. Room temperature single-photon detectors for high bit rate quantum key distribution. https://doi.org/10.1063/1.4855515

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