一种基于标记单光子源的态制备误差容忍量子密钥分发协议  

State preparation error tolerant quantum key distribution protocol based on heralded single photon source

作　　者：马啸 孙铭烁 刘靖阳 丁华建 王琴[1,2] Ma Xiao;Sun Ming-Shuo;Liu Jing-Yang;Ding Hua-Jian;Wang Qin(Institute of Quantum Information and Technology,Nanjing University of Posts and Telecommunications,Nanjing 210003,China;Key Laboratory of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education,Nanjing University of Posts and Telecommunications,Nanjing 210003,China)

机构地区：[1]南京邮电大学,量子信息技术研究所,南京210003 [2]南京邮电大学,宽带无线通信与传感网技术教育部重点实验室,南京210003

出　　处：《物理学报》2022年第3期22-27,共6页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2018YFA0306400,2017YFA0304100);国家自然科学基金(批准号:12074194,11774180);江苏省自然科学基金前沿技术项目(批准号:BK20192001);江苏省研究生科研创新计划(批准号:KYCX20_0726,KYCX19_0951)资助的课题。

摘　　要：在实际量子密钥分发系统中,由于设备、器件存在缺陷,在量子态制备过程中往往存在误差,而这些态制备误差会导致一定的系统安全性漏洞.本文在Tamaki等(Phys.Rev.A90052314)的工作基础之上,提出了一种基于标记单光子源的态制备误差容忍量子密钥分发协议.本文将发送端制备态误差进行参数刻画并带入量子密钥协议安全性分析之中,避免了实际应用中由于态制备装置的不理想可能引入的安全性漏洞,提高了系统的安全性.同时,为了方便起见,本文采用三强度诱骗态方案开展建模分析与数值仿真计算.仿真结果显示,本文提出的协议对态制备误差具有很好的鲁棒性.同时,由于标记单光子源具有真空脉冲概率低的优点,与此前基于弱相干态脉冲的同类协议相比,我们的协议在传输距离较远时能够显示出更优的性能.因而,该工作有望为未来发展长距离量子保密通信应用与研究提供重要的参考价值.In practical quantum key distribution systems,there inevitably exist errors in the quantum state preparation process due to imperfections in realistic equipment and devices.Those errors would lead to some security loopholes in the quantum key distribution systems.According to the work of Tamaki et al.(Phys.Rev.A90052314),here in this work we propose a state preparation error tolerant quantum key distribution protocol through using heralded single-photon sources.In this protocol,we characterize the size of the error in the preparation state of Alice and bring it into the security analysis,thereby avoiding possible security loopholes and improving the security of the system.Moreover,we take the three-intensity decoy-state method for example to introduce the method of constructing the model and estimating the parameters,and carry out corresponding numerical simulations.We make a comparison between the loss tolerant protocol with weak coherent source(WCS)and our present protocol using heralded single-photon source(HSPS).Simulation results show that under the same state preparation error,the key generation rate of the protocol based on WCS is higher than that of protocol based on HSPS at short transmission distances(e.g.less than 150 km).The main reason is that the detection efficiency of the local detector used in the latter scheme is low.However,in the case of long transmission distances(e.g.greater than 200 km),the key generation rate of scheme with WCS drops deeply,while the decline of the key generation rate of the present scheme is much flatter.As a result,the former can no longer generate keys after 211 km,while the latter can transmit a maximum distance of 228 km.Moreover,we also make a comparison between the present scheme and the GLLP protocol with HSPS.The simulation results show that the GLLP protocol with HSPS is very sensitive to the state preparation error and its key generation rate will rapidly decrease with the increase of the state preparation error.On the contrary,our present protocol shows almost

关 键 词：量子密钥分发 标记单光子源 误差容忍协议 态制备误差 

分 类 号：O413[理学—理论物理] TN918.4[理学—物理]