Chinese Optics Letters

Phase modulation polarization encoding module applied to one-to-many QKD network based on wavelength division multiplexing

Yi Zhang, Xiaojuan Qin, Jindong Wang, Ya-Fei Yu, Zhengjun Wei, Zhi‐Ming Zhang

Published Jan 1, 2022• 2 citations

Abstract

The quantum key distribution (QKD) network is a promising solution for secure communications.In this paper, we proposed a polarization-independent phase-modulated polarization encoding module, and it can be combined with a dense wavelength division multiplexer (DWDM) to achieve multi-user QKD.We experimentally test the encoding module with a repetition rate of 62.5 MHz, and its average quantum bit error rate (QBER) is as low as 0.4%.Finally, we implement a principle verification test for simultaneous QKD for 1 to 2 users in 100 min, and the average QBER of two users under the transmission distance of 1 km and 5 km is kept below 0.8%.Due to the use of polarization encoding, the module can also realize scalable network architecture in free-space QKD systems in the future.

DOI: 10.3788/col202220.122701

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