Quantum secure direct communication scheme with identity authentication

Aiming at the problem that traditional quantum secure direct communication schemes need to assume legitimacy of both parties in advance, a GHZ state (a involving least three subsystems or particles entanglement) based scheme with identity authentication is proposed. The first encodes into eight types, divides parts, and sends them times. Each time, eavesdropping added detect whether particle detection channel secure, when sending for second time verify receiver. Specifically, according value ID key IDA, specified (such as <inline-formula><tex-math id="Z-20230114055019-1">\begin{document}$ |0\rangle $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20221684_Z-20230114055019-1.jpg"/><graphic xlink:href="2-20221684_Z-20230114055019-1.png"/></alternatives></inline-formula> id="Z-20230114055019-2">\begin{document}$ |+ \rangle xlink:href="2-20221684_Z-20230114055019-2.jpg"/><graphic xlink:href="2-20221684_Z-20230114055019-2.png"/></alternatives></inline-formula> particles) are found two particles. Then their positions marked <i>L</i> they traverse down until all keys traversed, obtaining position sequence <i>L</i>. After Bob detection, measures on corresponding basis key, measurement results coded, compared IDA complete authentication. third time. receiver extracts detected particles, then jointly measured, original information recovered through previously given coding rules, so realize safe communication. design this simple efficient, can be realized without complex unitary transformation. correctness analysis proves correct theory. security analyses interception/measurement retransmission attack, Trojan horse denial service auxiliary impersonation other attacks prove resist common internal external attacks, solve leakage. transmission efficiency 1, bit utilization capacity carrying 3 bits information. Compared some previous schemes, has obvious advantages these aspects. biggest advantage sender does not information, it high practical application value.