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arXiv · 1706.06628

An advanced active quenching circuit for ultra-fast quantum cryptography

Mario Stipčević·Bradley G. Christensen·Paul G. Kwiat·Daniel J. Gauthier
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Abstract

Commercial photon-counting modules based on actively quenched solid-state avalanche photodiode sensors are used in a wide variety of applications. Manufacturers characterize their detectors by specifying a small set of parameters, such as detection efficiency, dead time, dark counts rate, afterpulsing probability and single-photon arrival-time resolution (jitter). However, they usually do not specify the range of conditions over which these parameters are constant or present a sufficient description of the characterization process. In this work, we perform a few novel tests on two commercial detectors and identify an additional set of imperfections that must be specified to sufficiently characterize their behavior. These include rate-dependence of the dead time and jitter, detection delay shift, and "twilighting." We find that these additional non-ideal behaviors can lead to unexpected effects or strong deterioration of the performance of a system using these devices. We explain their origin by an in-depth analysis of the active quenching process. To mitigate the effects of these imperfections, a custom-built detection system is designed using a novel active quenching circuit. Its performance is compared against two commercial detectors in a fast quantum key distribution system with hyper-entangled photons and a random number generator.

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Mario Stipčević, Bradley G. Christensen, Paul G. Kwiat, Daniel J. Gauthier. 2017-06-20. An advanced active quenching circuit for ultra-fast quantum cryptography. https://doi.org/10.1364/oe.25.021861

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