Opt Express. 2023 Feb 13;31(4):5414-5425. doi: 10.1364/OE.474665.
We report a directly modulated distributed feedback laser operating in gain-switching mode for preparing the coherent states required for the Gaussian-modulated coherent-state (GMCS) continuous-variable quantum key distribution (CV-QKD) protocol. The proposed single-component quantum transmitter design eliminates the need for external modulators, decreasing the complexity of GMCS CV-QKD systems. The experimental results demonstrate a potential asymptotic secret key rate value of 2.63 Mbps over an 11-km fiber link, making the directly modulated GMCS transmitter particularly suitable for metropolitan optical networks where compactness, robustness, and low cost are key desirable features.
我们报告了一种直接调制的分布式反馈激光，工作在增益开关模式下，用于制备高斯调制连续变量量子密钥分发（GMCS CV-QKD）协议所需的相干态。所提出的单分量量子发射机设计消除了对外部调制器的需求，降低了 GMCS CV-QKD 系统的复杂性。实验结果表明，在 11km 光纤链路中，潜在的渐近密钥率值为 2.63Mbps，使得直接调制的 GMCS 发射机特别适合于城域光网络，其中紧凑性、鲁棒性和低成本是关键的理想特性。
