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Practical decoy state method in quantum key distribution with heralded single photon source

Qin Wang·Xiang-Bin Wang·Guang-Can Guo
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Abstract

We propose a practical decoy state method with heralded single photon source for quantum key distribution (QKD). In the protocol, 3 intensities are used and one can estimate the fraction of single-photon counts. The final key rate over transmission distance is simulated under various parameter sets. Due to the lower dark count than that of a coherent state, it is shown that a 3-intensity decoy-state QKD with a heralded source can work for a longer distance than that of a coherent state.

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Qin Wang, Xiang-Bin Wang, Guang-Can Guo. 2006-10-17. Practical decoy state method in quantum key distribution with heralded single photon source. https://doi.org/10.1103/physreva.75.012312

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