量子密钥分发系统经典交互过程的实际安全性研究

With the development of application of quantum key distribution, more and more secure loophole and quantum hacking scheme have been found on the practical quantum key distribution setup even though the mainstream quantum key distribution protocols have been proved to be absolutely secure. At present, the security research of the practical setup is mainly focus on various devices (Single photon detector, phase modulator, beam splitter, and so on) in the quantum key distribution system, but the security issues of the classical interaction process for the practical quantum key distribution setup have been rarely studied. So the purpose of the proposed research project is to study the security of the classical interaction process for the practical quantum key distribution setup based on our previous research. Firstly, the active phase compensation for the phase-encoded scheme and the fiber channel active polarization feedback for the polarization-encoded scheme are selected as the typical representative of the classical interaction process for the practical quantum key distribution setup. And then the possible secure loophole and the scheme of hacking and defending are studied theoretically and experimentally. Based on the results for the above research, the safety standard for the classical interaction process of the practical quantum key distribution setup is put forward and the safety criterion is introduced to standardize the design of the classical interaction process. This research project provides a new and novel research perspective for the security of the practical quantum key distribution setup and the research results will enhance its practical security and promote the its application process.

随着量子密钥分发应用的不断深入，研究者发现，尽管很多主流量子密钥分发协议的理论安全性已被证明，但其实际设备却由于各个实际器件的技术缺陷存在诸多实际安全性问题。目前实际安全性的研究主要集中在各实际器件的不理想性带来的安全问题，但针对量子密钥分发系统经典交互过程的安全性研究尚未看到报道。本项目拟在前期工作基础上，研究量子密钥分发系统经典交互过程的实际安全性，首先以具体编码系统的主动相位补偿和偏振信道补偿等量子密钥分发前处理通用经典交互过程作为研究对象，深入研究其可能存在的安全漏洞，并展开攻击和防御的建模、理论分析和实验研究，提出相应的经典信息交互的安全规范性要求。基于该研究结果，进一步构建数学和物理模型为量子密钥分发设备研发中经典交互过程的流程设计提供安全性判据。该研究将为量子通信系统的实际安全性研究提供新的研究视角，其研究结果也将进一步增强量子密钥分发系统实际应用的安全性，推动其应用进程。

近年来，量子密钥分发得到了飞速的发展，受到了学术界和产业界的广泛关注，同时由于应用研究的深入，量子密钥分发系统在实际条件下的安全性也越来越引起重视，本项目就是在这种背景下立项的。. 本项目主要研究了量子密钥分发系统各环节经典交互过程的实际安全性问题，主要包括无需校准的内禀稳定编解码器的研究，相位补偿和偏振补偿等经典交互过程的实际安全性问题，单光子探测器后向散射荧光在信道偏振补偿架构下的实际安全性问题，光源和后处理环节的优化问题，量子密钥分发通信节点全经典化问题等。项目研究得到了一系列有意义的研究结果，例如，在光纤量子密钥分发系统中实验验证了后向散射荧光和光纤信道偏振补偿系统相结合条件下的信息泄露；得到了在强扰动环境下仍旧能够稳定工作的偏振编解码方案，并利用该方案完成了能够内禀稳定制备四个偏振态的测量设备无关量子密钥分发实验；同时得到了无需在多个用户节点之间进行交互补偿的即插即用的本地相位补偿系统方案，该方案已经在多个量子密钥分发系统中得到了实验验证，这些研究工作及其结果对量子密钥分发系统在实际应用发展具有重要的参考价值。. 在本项目执行期间，项目负责人发表期刊论文10篇，其中作为通信作者的论文9篇，获得发明专利授权6项，培养硕士研究生13名。