Due to the better robustness of entangled W state,it is considered to be better qualified as information carrier for quantum information processing and quantum secure communication. Recently,many kinds of quantum direct communication protocols based on four-particle W state or three-particle asymmetric W state have been proposed. However,these protocols either have low communication efficiency or are difficult to be implemented in physics experiment. By utilizing three-particle W state and the mechanism of quantum identity authentication,a new deterministic secure quantum communication protocol was proposed. This protocol consisted of five parts: authentication code generating,quantum states preparation,quantum states distribution,eavesdropping check and identity authentication,and information communication. The two participants only needed to perform the two-particle Bell measurement,the single-particle Z-basis or X-basis measurement,and the communication efficiency was also improved: One W state can transmit one classical bit of information. The security analysis shows that the present protocol is secure against various eavesdropper Eve's attacks and impersonation attacks,so it has better security.
Due to the better robustness of entangled W state,it is considered to be better qualified as information carrier for quantum information processing and quantum secure communication. Recently,many kinds of quantum direct communication protocols based on four-particle W state or three-particle asymmetric W state have been proposed. However,these protocols either have low communication efficiency or are difficult to be implemented in physics experiment. By utilizing three-particle W state and the mechanism of quantum identity authentication,a new deterministic secure quantum communication protocol was proposed. This protocol consisted of five parts: authentication code generating,quantum states preparation,quantum states distribution,eavesdropping check and identity authentication,and information communication. The two participants only needed to perform the two-particle Bell measurement,the single-particle Z-basis or X-basis measurement,and the communication efficiency was also improved: One W state can transmit one classical bit of information. The security analysis shows that the present protocol is secure against various eavesdropper Eve's attacks and impersonation attacks,so it has better security.
We present a new quantum secure direct communication protocol with three-particle entangled state. The communication parties utilize decoy photons to check eavesdropping. The sender encodes the secret message with unitary transformation, we can directly transmit secret message with Bell-basis measurement and Z-basis measurement. The protocol is efficient in that all entangled states are used to transmit the secret message and two bits message can be transmitted one time, the preparation of three-particle entangled state is realized technique, the protocol is feasible to operate. The protocol is also verified to be secure for a noise quantum channel.
In response to the demand for identity authentication in quantum secure direct communication, this paper proposes a quantum secure direct communication scheme based on a mixture of single photon and Bell state, by combining the bidirectional identity authentication. Before communication begins, both parties share a series of secret information to prepare a series of single photon and Bell state particles. Encoding four single photons and four Bell states yields eight types of encoded information, followed by identity authentication. The first step in identity authentication is to use a single photon to verify the legitimacy of the receiver. If the error exceeds the given threshold, it indicates the presence of eavesdropping. Otherwise, the channel is safe. Then, Bell state particles are used to verify the legitimacy of the sender, and the threshold is also used to determine whether there is eavesdropping. The present method is the same as previous one. If the error rate is higher than the given threshold, it indicates the existence of third-party eavesdropping. Otherwise, it indicates that the channel is secure. As for the specific verification method, it will be explained in detail in the article. Afterwards, Bell state particles are mixed with a single photon as a transmission carrier, and eavesdropping detection particles are added whenever the quantum state is sent. However, once the eavesdropper intercepts the transmitted particles, owing to incomplete information obtained, the eavesdropper is unable to recover the original information, and the eavesdropping behavior will be immediately detected, thus terminating communication. In this scheme, single photon and Bell states are fully utilized, and hybrid communication can effectively improve transmission efficiency, encoding capability, and quantum bit utilization. Security analysis shows that this scheme can resist common external and internal attacks such as interception/measurement replay attacks, auxiliary particle attacks, and identity impersonation attacks. The analysis of efficiency and encoding capacity shows that the transmission efficiency of this scheme is 1, the encoding capacity is 3 bits per state, and the quantum bit utilization rate is 1. Compared with other schemes, this scheme has significant advantages because it uses different particles for bidirectional authentication, making it more difficult for attackers to crack, and thus it has higher security than traditional schemes.
A novel efficient deterministic secure quantum communication scheme based on four-qubit cluster states and single-photon identity authentication is proposed. In this scheme, the two authenticated users can transmit two bits of classical information per cluster state, and its efficiency of the quantum communication is 1/3, which is approximately 1.67 times that of the previous protocol presented by Wang et al [ Chin. Phys. Lett. 23 (2006) 2658]. Security analysis shows the present scheme is secure against intercept-resend attack and the impersonator's attack. Furthermore, it is more economic with present-day techniques and easily processed by a one-way quantum computer.
Abstract Quantum communication has been extensively studied and continuously developed due to its theoretical absolute security. In this work, a novel multiparty quantum communication protocol based on quantum stabilizer codes (QSC) is proposed. Firstly, a trusted third party provides quantum identity authentication (QIA) for users. Secondly, users prepare quantum multiparticle entangled states for transmitting secret information. Thirdly, the secret information is encoded by the QSC to resist channel noise. A part of the encoded qubits is selected to detect the security of the communication. In this protocol, QIA prevents active attacks such as impersonation attacks; the physical laws of quantum entangled state ensure information security; the theory of QSC corrects the flipping errors of qubits, and improves the communication efficiency. In addition, we prove the security of the protocol, and further verify the communication efficiency. Compared with existing protocols, this protocol has better performance on communication efficiency.
By studying the properties of the mixture of Bell state particles and single photons,in the paper we design a quantum code scheme with high coding capacity,and propose a novel quantum secure direct communication protocol with high transmission efficiency.Alice prepares Bell state particles and single photons,and divides Bell state particles into two sequences SA and SB.SB is sent to Bob for the first security check through using quantum correlation properties of particles.When the check result shows that the quantum channel is safe,by using the designed quantum code scheme, Alice encodes her classical message on the mixed quantum state sequence of Bell sequence SA and single photon sequence SS.Then,some single photons that are used for security check are re-inserted randomly into the encoded sequence,and the order of particles is rearranged to ensure checking Eve's attack.Alice sends the new sequence to Bob.Bob delays and receives it.And then,the quantum channel conducts the second-time security check.The transmission error rate is calculated,and if the error rate is lower than the tolerance threshold,the channel is safe.Bob decodes and reads Alice's message.The first security check is to determine whether quantum channel is safe.The second security check is to test whether there are eavesdroppers during information transmission.Safety analysis is done by applying the quantum information theory for the proposed protocol.The error rate introduced by Eve and the amount of information by Eve are calculated.It is shown that this pro-tocol can effectively resist measurement-resend attack,intercept-resend attack, auxiliary particle attack,denial of service attack and Trojan attack.Among them,auxiliary particle attack is analyzed in detail.The transmission efficiency and coding capacity are also analyzed.The transmission efficiency is 2,the quantum bit rate is 1,and the coding capacity is that a quantum state can encode three bits of classical messages.We also compare the proposed protocol with many existing popular protocols in the sense of efficiency,e.g.,Ping-Pong protocol, Deng F G et al.'s two-step and one-pad-time quantum secure direct communication protocol,Wang J et al.'s quantum secure direct communication protocol based on entanglement swapping and Quan D X et al.'s one-way quantum secure direct communication protocol based on single photon.It is proved that this proposed protocol has higher transmission efficiency.In addition,neither complex U operation nor entanglement swapping is used,and implementation process is simplified.However,this protocol is devoted to theoretical research of quantum secure direct communication.There are still some difficulties in the practical application.For example,the storage technology of quantum states is not mature at present.It is not easy to prepare and measure Bell state particles nor to combine them with single photons,and so on.The implementation of this protocol depends on the development of quantum technology in the future.