基于非高斯量子操作的高速远距离跨媒介连续变量量子密钥分发机制

With rapid development of the theoretical and experimental continuous variable quantum key distribution in recent years, it has become an important research area in quantum information science. The continuous variable quantum key distribution system is more and more popular since it may break the limitations of the discrete variable counterpart such as unideal source, low detection efficiency, and so on. The quantum communication technique based on the continuous variable has potential practical values as well. However, we need more demands on the practical complex communication environment which requires the implementation of continuous variable quantum key distribution in the transmedium quantum channels instead of a single channel, such as optical fiber and free space. Consequently, this project investigates the integration mechanism of non-Gaussian quantum operations and continuous variable quantum key distribution in the transmedium quantum channels.It suggests an approach to explore the operating mechanism of the transmedium continuous variable quantum key distribution with non-Gaussian quantum operations, which provide the security and stability of the practical continuous variable quantum key distribution system while preventing the effect of noise and disturbance from complex environments and avoid the eavesdropping of the transmitted quantum signals.It clarifies the theoretical and experimental mechanism of continuous variable quantum key distribution, including scheme design, algorithm optimization, security analysis and experiment test according to different perameters of the transmedium quantum channels. The non-Gaussian quantum operation-based transmedium continuous variable quantum key distribution have strong stability and scalability in terms of high-rate long-distance of transmission. The proposed transmedium quantum key distribution can not only ensure the security of the quantum communications, but also realize the practical implementation of quantum key distribution, which plays an important role in quantum communication systematism.

量子密钥分发是量子信息科学一个重要领域，近年来在理论和技术上发展迅速，研究成果丰富。由于突破了离散变量量子密钥分发系统信源不理想和检测效率低等局限，连续变量量子密钥分发系统具有较好科学意义和实用价值。然而在对实用性拓展需求不仅适于单一量子信道，还要满足复杂环境的跨媒介量子信道。鉴于上述情况，本项目面向跨媒介量子信道，阐明非高斯量子操作与连续变量量子密钥分发系统融合机理，针对复杂环境下量子密钥分发系统的安全性和稳定性等若干难题，探索基于非高斯操作的跨媒介量子密钥分发机制。根据不同参数的跨媒介量子信道，面向基于非高斯量子操作的量子通信系统，阐明连续变量量子密钥分发机理、算法设计、安全性分析及实验。本项目的跨媒介量子密钥分发系统，在高速和远距离等性能方面具有较好优势。对跨媒介连续变量量子密钥分发机制的研究不仅确保了复杂环境下量子通信的安全性，还具有较好实用性，它是量子安全通信体系重要组成部分。

跨媒介量子密钥分发技术作为未来量子通信领域的发展方向，已逐渐得到重视。本项目聚焦于复杂环境下的连续变量量子密钥分发技术，以非高斯操作为手段，研究了基于非高斯量子操作的高速远距离跨媒介连续变量量子密钥分发机制。根据跨媒介量子密钥分发系统的特点，将非高斯量子操作和跨媒介量子密钥分发系统融合，探索基于非高斯量子操作的跨媒介连续变量量子密钥分发系统的拓扑结构特征，阐明高速远距离跨媒介量子密钥分发机理、算法设计、安全分析及实验技术，解决量子通信技术的安全问题和实用问题。面向跨媒介量子信道引入非高斯调制连续变量量子密钥分发技术，可解决如下问题： 第一：探明跨媒介量子密钥分发系统结构特征，简化量子通信系统设计过程；第二：增强复杂环境影响下量子通信系统的稳定性，减少环境因素影响；第三：拓展量子密钥分发技术的应用空间，加速量子通信技术实用化进程。透过非高斯量子操作的结构特点和物理属性探索跨媒介连续变量量子密钥分发机制的本质，从安全性和实用性的角度出发为建立定性和定量的跨媒介量子密钥分发系统技术框架奠定基础。