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arXiv · 1407.1924

Mismatched-basis statistics enable quantum key distribution with uncharacterized qubit sources

Zhen-Qiang Yin·Chi-Hang Fred Fung·Xiongfeng Ma·Chun-Mei Zhang·Hong-Wei Li·Wei Chen·Shuang Wang·Guang-Can Guo·Zheng-Fu Han
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Abstract

In the postprocessing of quantum key distribution, the raw key bits from the mismatched-basis measurements, where two parties use different bases, are normally discarded. Here, we propose a postprocessing method that exploits measurement statistics from mismatched-basis cases, and prove that incorporating these statistics enables uncharacterized qubit sources to be used in the measurement-device-independent quantum key distribution protocol and the Bennett-Brassard 1984 protocol, a case which is otherwise impossible.

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Zhen-Qiang Yin, Chi-Hang Fred Fung, Xiongfeng Ma, Chun-Mei Zhang, Hong-Wei Li, Wei Chen, Shuang Wang, Guang-Can Guo, Zheng-Fu Han. 2014-11-27. Mismatched-basis statistics enable quantum key distribution with uncharacterized qubit sources. https://doi.org/10.1103/physreva.90.052319

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