物理学报2017，Vol.66Issue(13)：41-46,6.DOI:10.7498/aps.66.130304
基于Bell态粒子和单光子混合的量子安全直接通信方案的信息泄露问题
Information leakage problem in quantum secure direct communication protocol based on the mixture of Bell state particles and single photons
摘要
Abstract
Recently, a quantum secure direct communication (QSDC) protocol based on the mixture of Bell state particles and single photons [Acta Phys. Sin. 65230301(2016)] was put forward. In this QSDC protocol, the single photons and the Bell states were both used as information carriers. To be specific, each Bell state as well as single photon was encoded by three bits of classical information. After the sender told the receiver how to measure the particles, the receiver could read out the secret message sent by the sender. Speciously, the information transmission e?ciency of this protocol was high. Unfortunately, there exists the information leakage problem in this protocol. When the sender announces that the receiver uses the Z-basis to measure a single photon, everyone knows that the sent secret message is 000 or 001, that is, the first two bits are leaked out; when the sender announces that the receiver uses the X-basis to measure a single photon, everyone knows that the sent secret message is 010 or 011, that is, the first two bits are leaked out too;when the sender announces that the receiver uses the Bell-basis to measure a pair of particles from a Bell state, everyone knows that the sent secret message is 100, 101, 110 or 111, that is, the first bit is leaked out. In a word, two of the three bits of classical information encoded in a single photon, and one of the three bits of classical information encoded in a Bell state are leaked out. Therefore, this scheme is not secure. On the basis of keeping the original idea and changing the contents of the protocol as less as possible, we put forward an improved message encoding rule to solve the information leakage problem, that is, the single photon is only encoded by one bit of classical information, and the Bell state is only encoded by two bits of classical information. In fact, this makes the information capacity of the improved protocol achieves the Helovo bound. So it has high coding capacity. We hope researchers pay more attention to the information leakage problem in quantum secure communication protocols, and thus design truly secure ones.关键词
信息泄露/单光子/Bell态/量子安全直接通信Key words
information leakage/single photon/Bell state/quantum secure direct communication引用本文复制引用
刘志昊,陈汉武..基于Bell态粒子和单光子混合的量子安全直接通信方案的信息泄露问题[J].物理学报,2017,66(13):41-46,6.基金项目
国家自然科学基金(批准号: 61502101, 61170321)、江苏省自然科学基金(批准号: BK20140651, BK20140823)、PAPD和CICAEET资助的课题. Project supported by the National Natural Science Foundation of China (Grant Nos. 61502101, 61170321), Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20140651, BK20140823), PAPD and CICAEET. （批准号: 61502101, 61170321）
