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Stable polarization-encoded quantum key distribution in fiber

Guang Wu·Jie Chen·Yao Li·Heping Zeng
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Abstract

Polarizations of single-photon pulses have been controlled with long-term stability of more than 10 hours by using an active feedback technique for auto-compensation of unpredictable polarization scrambling in long-distance fiber. Experimental tests of long-term operations in 50, 75 and 100 km fibers demonstrated that such a single-photon polarization control supported stable polarization encoding in long-distance fibers to facilitate stable one-way fiber system for polarization-encoded quantum key distribution, providing quantum bit error rates below the absolute security threshold.

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Guang Wu, Jie Chen, Yao Li, Heping Zeng. 2006-06-13. Stable polarization-encoded quantum key distribution in fiber. https://arxiv.org/abs/quant-ph/0606108

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