基于EPR导引的连续变量安全量子克隆  

Secure Continuous Variable Quantum Cloning Based on EPR Steering

作　　者：王俊 翟淑琴[1,2] Wang Jun;Zhai Shuqin(College of Physics and Electronic Engineering,Shanxi University,Taiyuan 030006,Shanxi,China;State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,Shanxi,China)

机构地区：[1]山西大学物理电子工程学院,山西太原030006 [2]山西大学光电研究所量子光学与光量子器件国家重点实验室,山西太原030006

出　　处：《光学学报》2024年第3期280-287,共8页Acta Optica Sinica

基　　金：山西省自然科学基金(202203021211306);国家自然科学基金(12074233);国家重点研发计划(2021YFC2201802);2022年山西省高等学校教学改革创新项目(J20220082);山西1331项目。

摘　　要：利用量子信道和经典信道相结合的方法,采用部分脱体传输设计了连续变量1→2量子克隆方案,在此基础上研究了克隆保真度与EPR导引之间的关系。研究结果表明:双向量子导引态是实现相干态安全量子克隆的必要资源。对于克隆输出模Clone 1,取最优增益时克隆保真度超过不可克隆阈值的实现需要共享纠缠源的双向导引,但并不是所有双向导引的资源都能使克隆的保真度大于2/3。在输出模Clone 1的最优增益下,观察了输出模Clone 1和输出模Clone 2的保真度随分束器反射率和压缩参数的变化,发现使用纠缠度较小但可导引的资源可以实现较高的克隆保真度,且克隆过程中也不需要较高的反射率。此研究结果对安全量子通信网络的构建具有一定的参考意义。Objective Quantum communication is based on the three principles of uncertainty,measurement collapse,and nocloning in quantum mechanics.Compared with traditional classical communication methods,quantum communication features security and high efficiency and has great application significance and prospect in information security.In recent years,domestic and international scientists have conducted a lot of research on theories and experiments and made outstanding achievements in long-distance transmission and practical network of quantum communication.Quantum teleportation and quantum cloning have caught extensive attention as important protocols in quantum communication.With the help of quantum entanglement and classical communication,the transmission of any unknown quantum state from one location to another can be realized.As important resources of quantum information,quantum entanglement and EPR steering are widely adopted in various quantum communication tasks.The natural asymmetry of EPR steering makes quantum steering a helpful resource in various quantum information processes.In the tasks of single-side deviceindependent quantum-key distribution,secure quantum teleportation,and subchannel discrimination,quantum steering can improve key acquisition rate,and enhance the protocol efficiency and security.In 2000,Cerf N J et al.proposed quantum cloning of Gaussian states with continuous variables and gave the fidelity boundary of quantum cloning as 2/3.In 2001,the Grangier P group presented the quantum and classical fidelity boundary of coherent state continuous variable quantum cloning under Heisenberg representation.For coherent state input,quantum teleportation is achieved when the fidelity exceeds the classical limit of 1/2,which is the best value that can be obtained without entanglement.However,it is necessary to have certain requirements for entangled beams to realize quantum teleportation with a fidelity greater than 2/3.In 2004,the Furusawa group applied three single-mode OPOs to obtain a continuous vari

关 键 词：量子光学 量子克隆 量子关联 双向导引 

分 类 号：O437[机械工程—光学工程]