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arXiv · 2304.11655

Experimental demonstration of fully passive quantum key distribution

Feng-Yu Lu·Ze-Hao Wang·Víctor Zapatero·Jia-Lin Chen·Shuang Wang·Zhen-Qiang Yin·Marcos Curty·De-Yong He·Rong Wang·Wei Chen·Guan-Jie Fan-Yuan·Guang-Can Guo·Zheng-Fu Han
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Abstract

The passive approach to quantum key distribution (QKD) consists of removing all active modulation from the users' devices, a highly desirable countermeasure to get rid of modulator side-channels. Nevertheless, active modulation has not been completely removed in QKD systems so far, due to both theoretical and practical limitations. In this work, we present a fully passive time-bin encoding QKD system and report on the successful implementation of a modulator-free QKD link. According to the latest theoretical analysis, our prototype is capable of delivering competitive secret key rates in the finite key regime.

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Feng-Yu Lu, Ze-Hao Wang, Víctor Zapatero, Jia-Lin Chen, Shuang Wang, Zhen-Qiang Yin, Marcos Curty, De-Yong He, Rong Wang, Wei Chen, Guan-Jie Fan-Yuan, Guang-Can Guo, Zheng-Fu Han. 2023-04-23. Experimental demonstration of fully passive quantum key distribution. https://arxiv.org/abs/2304.11655

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