量子信号和经典光信号共纤同传技术是光纤量子保密通信实用化进程中的关键技术, 该技术可以显著降低量子保密通信网络的建设成本。通过比较离散变量量子信号和连续变量量子信号分别与经典光信号共纤同传的基本原理, 提出了基于少模光纤(FMF)模分复用(MDM)的离散变量量子信号、连续变量量子信号以及经典光信号三者共纤同传的方法, 降低了非线性损伤及噪声, 有效地利用了现有的光纤资源。结合离散变量量子密钥分发技术和连续变量量子密钥分发技术的优势, 构建了更加稳定有效的量子保密通信网络。

The key technology in practical optical fiber quantum private communication is the co-fiber-transmission technology for quantum signal and classical optical signal. The cost of quantum private communication network construction can be decreased remarkably by the co-fiber-transmission technology. The co-fiber-transmission principles of propagating classical optical signal together with discrete-variable quantum signal and continuous-variable quantum signal are compared. The co-fiber-transmission of discrete-variable quantum signal, continuous-variable quantum signal and classical optical signal based on mode division multiplexing in few-mode fiber (FMF) is proposed to reduce nonlinear damage and noise. This new scheme can use the fiber resource efficiently. A stable and efficient quantum private communication network is established when we integrate the technical advantages of discrete-variable quantum key distribution and continuous-variable quantum key distribution.