Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections...Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.展开更多
There are still debates on whether the observed zero energy peak in the experiment by Stevan et al. [Science 346 （2014） 602] reveals the existence of the long pursued Ala.jorana bound states （MBSs）. We propose tha...There are still debates on whether the observed zero energy peak in the experiment by Stevan et al. [Science 346 （2014） 602] reveals the existence of the long pursued Ala.jorana bound states （MBSs）. We propose that, by mounting two scanning tunneling microscopic tips on top of the topological superconducting chain and measuring the transmission spectrum between these two metallic tips, there are two kinds of characteristics on the spectrum that are caused by A.IBSs uniquely： One is symmetric peaks with respect to zero energy and the other is 4~r period caused by a nearby dosephson junction. The former refers to the fact that MBSs are eomposited by Alajorana fermions which distributed in the particle and hole subspaees equally. The latter is based on the well known 4w period of Josephson effect in topological superconductor. We think that such two characteristics can be used as criteria to distinguish MBSs from other candidates, such as impurities, Kondo effect and traditional Andreev bound states.展开更多
基金the National Key Research and Development Program of China(Grant No.2020YFA0309702)NSAF(Grant No.U2130205)+3 种基金the National Natural Science Foundation of China(Grant Nos.62101597,61605248,and 61505261)the China Postdoctoral Science Foundation(Grant No.2021M691536)the Natural Science Foundation of Henan(Grant Nos.202300410534 and 202300410532)the Anhui Initiative in Quantum Information Technologies。
文摘Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.
文摘There are still debates on whether the observed zero energy peak in the experiment by Stevan et al. [Science 346 （2014） 602] reveals the existence of the long pursued Ala.jorana bound states （MBSs）. We propose that, by mounting two scanning tunneling microscopic tips on top of the topological superconducting chain and measuring the transmission spectrum between these two metallic tips, there are two kinds of characteristics on the spectrum that are caused by A.IBSs uniquely： One is symmetric peaks with respect to zero energy and the other is 4~r period caused by a nearby dosephson junction. The former refers to the fact that MBSs are eomposited by Alajorana fermions which distributed in the particle and hole subspaees equally. The latter is based on the well known 4w period of Josephson effect in topological superconductor. We think that such two characteristics can be used as criteria to distinguish MBSs from other candidates, such as impurities, Kondo effect and traditional Andreev bound states.
