基于不可信纠缠源的高斯调制连续变量量子密钥分发  

Gaussian-modulated continuous-variable quantum key distribution based on untrusted entanglement source

作　　者：廖骎 柳海杰 王铮 朱凌瑾 Liao Qin;Liu Hai-Jie;Wang Zheng;Zhu Ling-Jin(College of Computer Science and Electronic Engineering,Hunan University,Changsha 410082,China;Hunan Institute of Metrology and Test,Changsha 410014,China)

机构地区：[1]湖南大学信息科学与工程学院,长沙410082 [2]湖南省计量检测研究院,长沙410014

出　　处：《物理学报》2023年第4期1-9,共9页Acta Physica Sinica

基　　金：国家自然科学基金项目(批准号:62101180);湖南省自然科学基金项目(批准号:2022JJ30163);国防科技大学高性能计算国家重点实验室(批准号:202101-25)资助的课题。

摘　　要：在实际的量子通信系统中,连续变量量子密钥分发的信源安全可能会因为器件的缺陷或隐藏的攻击而受到威胁.针对这个问题,本文提出了基于不可信纠缠源的高斯调制连续变量量子密钥分发方案,通过将高斯纠缠源置于不可信的量子信道来模拟纠缠源被攻击者所控制的场景,从而验证实际复杂环境下高斯调制连续变量量子密钥分发的安全性.本文详细分析不可信纠缠源对系统安全性的影响并引入了两种光学放大器来辅助提升所提方案的实际性能.仿真实验结果表明,本文所提方案即使在高斯纠缠源不可信的情况下仍然能够产生安全的量子密钥,同时,光学放大器也能够有效提升接收端探测器的量子效率.该工作旨在推动高斯调制连续变量量子密钥分发系统的实用化进程,为高斯调制连续变量量子密钥分发系统的实际部署和应用提供理论指导.In a practical quantum communication system,the security of signal source of continuous-variable quantum key distribution may be jeopardized due to device flaws and hidden attacks.In this paper,an improved scheme for Gaussian-modulated continuous-variable quantum key distribution based on an untrusted entangled source is proposed.In particular,the entanglement source is placed in an untrusted quantum channel to simulate that it is controlled by an eavesdropper,thereby verifying the security of Gauss ian-modulated continuous-variable quantum key distribution in a complex environment.This work in detail analyzes the influence of untrusted entanglement source on practical Gaussian-modulated continuous-variable quantum key distribution system,and the numerical simulation shows that the performance of Gaussian-modulated continuous-variable quantum key distribution will dramatically decrease once the entanglement source has moved out of the sender,and it will slightly rise as the untrusted entanglement source slowly moves away from the sender.This paper further introduces two kinds of optical amplifiers,which are phase-sensitive amplifier and phase-insensitive amplifier,to compensate for the imperfection of the coherent detector.These amplifiers are beneficial to enhancing the quantum efficiency of the receiver’s detector.Specifically,the security key rate of Gaussian-modulated continuous-variable quantum key distribution with homodyne detection can be well improved by phase-sensitive amplifier,and the security key rate of Gaussian-modulated continuous-variable quantum key distribution with heterodyne detection can be well improved by phase-insensitive amplifier.To summary,this paper proposes a scheme for Gaussian-modulated continuous-variable quantum key distribution with untrusted entanglement source,experimental results show that the proposed scheme can generate secure quantum keys even if the Gaussian entanglement source is untrusted,and the two optical amplifiers can effectively improve the quantum efficiency of

关 键 词：连续变量量子密钥分发 不可信纠缠源 光学放大器 量子通信 

分 类 号：O413[理学—理论物理] TN918.4[理学—物理]