Fault tolerant quantum secure direct communication with quantum encryption against collective noise  

作　　者：黄伟 温巧燕 贾恒越 秦素娟 高飞 

机构地区：[1]State Key Laboratory of Networking and Switching Technology,Beijing University of Posts and Telecommunications [2]State Key Laboratory of Integrated Services Network,Xidian University

出　　处：《Chinese Physics B》2012年第10期101-109,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 61170270,61100203,60903152,61003286,and61121061);the Program for New Century Excellent Talents in University (Grant No. NCET-10-0260);the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20090005110010);the Natural Science Foundation of Beijing (Grant Nos. 4112040 and 4122054);the Foundation of Science and Technology on Communication Security Laboratory (Grant No. 9140C110101110 C1104);the Fundamental Research Funds for the Central Universities (Grant Nos. BUPT2011YB01,BUPT2011RC0505,2011PTB-00-29,and 2011RCZJ15)

摘　　要：We present two novel quantum secure direct communication（QSDC） protocols over different collective-noise channels.Different from the previous QSDC schemes over collective-noise channels,which are all source-encrypting protocols,our two protocols are based on channel-encryption.In both schemes,two authorized users first share a sequence of EPR pairs as their reusable quantum key.Then they use their quantum key to encrypt and decrypt the secret message carried by the decoherence-free states over the collective-noise channel.In theory,the intrinsic efficiencies of both protocols are high since there is no need to consume any entangled states including both the quantum key and the information carriers except the ones used for eavesdropping checks.For checking eavesdropping,the two parties only need to perform two-particle measurements on the decoy states during each round.Finally,we make a security analysis of our two protocols and demonstrate that they are secure.We present two novel quantum secure direct communication（QSDC） protocols over different collective-noise channels.Different from the previous QSDC schemes over collective-noise channels,which are all source-encrypting protocols,our two protocols are based on channel-encryption.In both schemes,two authorized users first share a sequence of EPR pairs as their reusable quantum key.Then they use their quantum key to encrypt and decrypt the secret message carried by the decoherence-free states over the collective-noise channel.In theory,the intrinsic efficiencies of both protocols are high since there is no need to consume any entangled states including both the quantum key and the information carriers except the ones used for eavesdropping checks.For checking eavesdropping,the two parties only need to perform two-particle measurements on the decoy states during each round.Finally,we make a security analysis of our two protocols and demonstrate that they are secure.

关 键 词：quantum cryptography quantum secure direct communication quantum encryption collective noise 

分 类 号：O413[理学—理论物理] TN918[理学—物理]