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arXiv · 1608.00366

Polarization basis tracking scheme for quantum key distribution with revealed sifted key bits

Yu-Yang Ding·Wei Chen·Hua Chen·Chao Wang·Ya-Ping li·Zhen-Qiang Yin·Shuang Wang·Guang-Can Guo·Zheng-Fu Han
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Abstract

Calibration of the polarization basis between the transmitter and receiver is an important task in quantum key distribution (QKD). An effective polarization-basis tracking scheme will decrease the quantum bit error rate (QBER) and improve the efficiency of a polarization encoding QKD system. In this paper, we proposed a polarization-basis tracking scheme using only unveiled sifted key bits while performing error correction by legitimate users, rather than introducing additional reference light or interrupting the transmission of quantum signals. A polarization-encoding fiber BB84 QKD prototype was developed to examine the validity of this scheme. An average QBER of 2.32% and a standard derivation of 0.87% have been obtained during 24 hours of continuous operation.

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Yu-Yang Ding, Wei Chen, Hua Chen, Chao Wang, Ya-Ping li, Zhen-Qiang Yin, Shuang Wang, Guang-Can Guo, Zheng-Fu Han. 2016-08-02. Polarization basis tracking scheme for quantum key distribution with revealed sifted key bits. https://doi.org/10.1364/ol.42.001023

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