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Low Timing Jitter Detector for Gigahertz Quantum Key Distribution

R. J. Collins·R. H. Hadfield·V. Fernandez·S. W. Nam·G. S. Buller
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Abstract

A superconducting single-photon detector based on a niobium nitride nanowire is demonstrated in an optical-fibre-based quantum key distribution test bed operating at a clock rate of 3.3 GHz and a transmission wavelength of 850 nm. The low jitter of the detector leads to significant reduction in the estimated quantum bit error rate and a resultant improvement in the secrecy efficiency compared to previous estimates made by use of silicon single-photon avalanche detectors.

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R. J. Collins, R. H. Hadfield, V. Fernandez, S. W. Nam, G. S. Buller. 2007-02-23. Low Timing Jitter Detector for Gigahertz Quantum Key Distribution. https://arxiv.org/abs/quant-ph/0702216

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