基于混合纠缠的参考系无关测量设备无关量子密钥分发协议研究

Measurement-Device-Independent quantum key distribution (MDI-QKD) is immune to all the detector attacks. However, an implementation of MDI-QKD involves several error sources to affect the performance of MDI-QKD. Here, we adopt the hybrid encoding approach of polarization-orbit angular momentum(OAM) qubit and present an available extension MDI-QKD protocol. We test and analyze the commercial QKD product and practical optical or electrical devices to find the noise associated with unknown relative rotations existed in these systems, then theoretical model will be set up to analyze the reference-frame-independent MDI-QKD scheme with hybrid entanglement. At the same time, by combining MDI-QKD with heralding processing, we present a modified MDI-QKD scheme with a photonic system composed of two vector vortex beams, which shows a structure of hybrid entangled entanglement corresponding to intrasystem entanglement and intersystem entanglement. Furthermore, we will propose and demonstrate new MDI-QKD protocols and experimental schemes which are immune to the noise.

测量设备无关量子密钥分发协议（Measurement Device independent Quantum Key Distribution，MDI-QKD ）可以克服探测器侧信道安全漏洞，实现非可信中继节点组网，是目前量子保密通信领域的一个研究热点。本项目针对MDI-QKD实验过程中的参考系非对齐噪声、偏振随机旋转信道噪声等实际问题，提出基于偏振-轨道角动量混合纠缠的参考系无关MDI-QKD 协议的研究思路。首先对现有QKD系统开展环境噪声测试和建模，在此基础上研究单光子混合纠缠的旋转不变特性及其产生方案，设计并实验单光子混合纠缠的参考系无关MDI-QKD协议；最后拓展研究双光子混合纠缠的参考系无关预报MDI-QKD协议。本项目的预期研究结果可为实际的MDI-QKD的应用提供新的理论依据和实验方案。

本项目开展具有抗偏振旋转噪声的参考系无关测量设备无关量子密钥分发（Measurement Device Independent Quantum Key Distribution, MDI-QKD）协议及实验方案的研究，从理论方面分析三类单光子体系偏振- 轨道角动量混合纠缠的产生方案及其实验可行性，并提出相应的参考系无关 MDI-QKD 改进协议，并完成具有抗偏振随机旋转噪声的参考系无关 MDI-QKD 部分实验方案，进一步理论研究双光子体系偏振-轨道角动量混合纠缠的体系间纠缠特性，提出参考系无关预报 MDI-QKD 改进协议来抵抗环境噪声的影响。本项目的研究为实际的量子密钥分发系统克服偏振旋转噪声提供了一种有效方案，为下一步自由空间参考系无关量子密钥分发协议的可行性与安全性研究提供了新的途径。