We propose an improved quantum key distribution (QKD) protocol based on orbital angular momentum (OAM) entangled states. Three Lucas-valued OAM entangled photons are generated by two cascaded spontaneous parameter down-conversion processes. Two photons are detained and detected by Alice, while the other is transmitted to Bob and then detected. A new scheme is designed to sift the original key bits. Compared to existing protocols, we believe our protocol greatly improves coding efficiency and is verifiable. The analysis results show that our protocol is immune to the photon-number-splitting attack, the intercept-resend attack and the classical information leakage. This work provides an efficient path to high-dimensional QKD systems.

中文翻译：

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基于卢卡斯值轨道角动量态的改进量子密钥分配

我们提出了一种基于轨道角动量（OAM）纠缠态的改进的量子密钥分配（QKD）协议。由两个级联的自发参数下转换过程生成三个Lucas值的OAM纠缠光子。两个光子被爱丽丝（Alice）保留并检测到，而另一个被传输给鲍勃（Bob），然后被检测到。设计了一种新方案来筛选原始密钥位。与现有协议相比，我们认为我们的协议大大提高了编码效率，并且是可验证的。分析结果表明，该协议不受光子数分裂攻击，重发拦截和经典信息泄漏的影响。这项工作为高维QKD系统提供了有效的途径。