Coexistence of 1 Tbps classical optical communication and quantum key distribution over a 100.96 km few-mode fiber
Tianqi Dou, Song Gao, Chengliang Zhang, Jiangang Tong, R. Liu, Lei Shen, Juhao Li, Zhengjun Pan, Min Liao, Jianjun Tang, Shibiao Tang
Abstract
The integration of quantum key distribution (QKD) and classical optical communication has attracted widespread attention. In this Letter, we experimentally demonstrate a real-time co-propagation of 1 Tbps for 10 classical channels with one discrete-variable QKD channel in the weakly coupled few-mode fiber (FMF). Based on the selection of optimal device parameters and wavelength assignment of classical channels, as well as the optimization of equipment performance, a secure key rate of as high as 2.7 kbps of coexistence transmission of QKD and classical optical communication can be achieved using a 100.96 km weakly coupled FMF. Therefore, this study is a step toward realizing long-distance quantum-classical coexistence transmission.