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Passive decoy state quantum key distribution: Closing the gap to perfect sources

Wolfgang Mauerer·Christine Silberhorn
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Abstract

We propose a quantum key distribution scheme which closely matches the performance of a perfect single photon source. It nearly attains the physical upper bound in terms of key generation rate and maximally achievable distance. Our scheme relies on a practical setup based on a parametric downconversion source and present-day, non-ideal photon-number detection. Arbitrary experimental imperfections which lead to bit errors are included. We select decoy states by classical post-processing. This allows to improve the effective signal statistics and achievable distance.

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Wolfgang Mauerer, Christine Silberhorn. 2006-10-17. Passive decoy state quantum key distribution: Closing the gap to perfect sources. https://doi.org/10.1103/physreva.75.050305

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