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arXiv · 0908.4063

200km Decoy-state quantum key distribution with photon polarization

Teng-Yun Chen·Jian Wang·Yang Liu·Wen-Qi Cai·Xu Wan·Luo-Kan Chen·Jin-Hong Wang·Shu-Bin Liu·Hao Liang·Lin Yang·Cheng-Zhi Peng·Zeng-Bing Chen·Jian-Wei Pan
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Abstract

We demonstrate the decoy-state quantum key distribution over 200 km with photon polarization through optical fiber, by using super-conducting single photon detector with a repetition rate of 320 Mega Hz and a dark count rate of lower than 1 Hz. Since we have used the polarization coding, the synchronization pulses can be run in a low frequency. The final key rate is 14.1 Hz. The experiment lasts for 3089 seconds with 43555 total final bits.

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Teng-Yun Chen, Jian Wang, Yang Liu, Wen-Qi Cai, Xu Wan, Luo-Kan Chen, Jin-Hong Wang, Shu-Bin Liu, Hao Liang, Lin Yang, Cheng-Zhi Peng, Zeng-Bing Chen, Jian-Wei Pan. 2009-08-27. 200km Decoy-state quantum key distribution with photon polarization. https://doi.org/10.1364/oe.18.008587

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