基于混合编码的测量设备无关量子密钥分发的简单协议  

A simple protocol for measuring device independent quantum key distribution based on hybrid encoding

作　　者：杜聪 王金东[1] 秦晓娟[2] 魏正军[1] 於亚飞[1] 张智明[1] Du Cong;Wang Jin-Dong;Qin Xiao-Juan;Wei Zheng-Jun;Yu Ya-Fei;Zhang Zhi-Ming(Guangdong Provincial Key Laboratory of Quantum Control Engineering and Materials,South China Normal University,Guangzhou 510006,China;Engineering and Technology Department,Guangdong Polytechnic Institute,Guangzhou 510091,China)

机构地区：[1]华南师范大学,广东省量子调控工程与材料重点实验室,信息光电子科技学院,广州510006 [2]广东理工职业学院工程技术系,广州510091

出　　处：《物理学报》2020年第19期1-15,共15页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61771205);广东省自然科学基金(批准号:2015A030313388);广东省科技计划(批准号:2015B010128012,2017KZ010101).

摘　　要：测量设备无关量子密钥分发协议移除了所有测量设备的漏洞,极大地提高了量子密钥分发系统的实际安全性,然而,该协议的安全密钥率相比于其他量子密钥分发协议来说仍然是较低的.目前,利用高维编码来提升量子密钥分发协议的性能已经在理论和实验上都得到证明,最近有人提出了基于高维编码的测量设备无关量子密钥分发协议,但是由于所提出的协议对实验设备性能有更高的要求,所以在实际应用上仍然存在许多困难.本文提出一种基于偏振和相位两种自由度的混合编码测量设备无关量子密钥分发协议,并且利用四强度诱骗态方法分析该协议在实际条件下的安全性,最后数值仿真结果表明,该协议在实际条件下40 km和50 km处的最优安全码率相比于原MDI-QKD协议分别提升了52.83%和50.55%.而且,相比于其他基于高维编码的测量设备无关量子密钥分发协议来说,本文提出的协议只要求本地用户拥有相位编码装置和偏振编码装置,探测端也只需要四台单光子探测器,这些装置都可以利用现有的实验条件实现,说明该协议的实用价值也很高.Quantum key distribution technology refers to a method to share keys between communication parties by transmitting quantum states in public channels.Although unconditional security is the main advantage of QKD,its application prospect has been controversial in practical implementation due to the potential security risks caused by device imperfections.Fortunately,the measurement device independent quantum key distribution protocol removes the vulnerability of all measurement devices and greatly improves the practical security of the quantum key distribution system.However,the security key rate of this protocol is still lower than that of other quantum key distribution protocols.At present,using high-dimensional coding to improve the performance of the quantum key distribution protocol has been proved in theory and experiment,and recently,it has been proposed to use high-dimensional coding to improve the performance of measurement device independent quantum key distribution protocol,but because these protocols have higher requirements for the laboratory equipment performance,that the high-dimensional encoding is applied to the aforementioned protocol still has many difficulties in practical application.In this paper,we propose a hybrid coding based on the polarization and two-degree phase of freedom measurement device independent quantum key distribution protocol.In the first place in an ideal case,we introduce in detail the protocol decoding rules,then introduce 4intensity decoy-state method to solve the problem of actual light source multiphoton,in addition we also consider the statistical fluctuation effect under the condition of limited code length,channel loss,actual dark count of single photon detector and detection efficiency problem.Finally,the optimal security code rate and its corresponding optimal parameters are obtained by full parameter optimization method,And the numerical simulation results show that the security key rate of this protocol is increased by 50%by considering the practical implementation

关 键 词：量子密钥分发 测量设备无关 高维编码 混合编码 

分 类 号：O413[理学—理论物理] TN918.4[理学—物理]