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Quantum key distribution network with wavelength addressing

Xiao-Fan Mo·Tao Zhang·Fang-Xing Xu·Zheng-Fu Han·Guang-Can Guo
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Abstract

Most traditional applications of quantum cryptography are point-to-point communications, in which only two users can exchange keys. In this letter, we present a network scheme that enable quantum key distribution between multi-user with wavelength addressing. Considering the current state of wavelength division multiplexing technique, dozens or hundreds of users can be connected to such a network and directly exchange keys with each other. With the scheme, a 4-user demonstration network was built up and key exchanges were performed.

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Xiao-Fan Mo, Tao Zhang, Fang-Xing Xu, Zheng-Fu Han, Guang-Can Guo. 2006-10-15. Quantum key distribution network with wavelength addressing. https://arxiv.org/abs/quant-ph/0610096

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