Research On Quantum Communication Protocols In Collective Noise Channel

With the continuous maturity and popularization of the next-generation information technologies such as cloud computing and the Internet of Things,human society has entered the era of big data.While enjoying the convenience brought by big data,people also bear the risk of personal privacy being leaked.Quantum communication is a new communication method that has emerged in recent years.It combines quantum mechanics with classical informatics,and has unconditional security in theory.This kind of unconditional security makes quantum communication has very important research value in the era of frequent information security problems,and has attracted great attention from domestic and foreign scholars.After more than 30 years of development,the theoretical research of quantum communication has continued to innovate,and the new branches,such as controlled quantum dialogue and quantum conference with good application prospects,have been derived,which have greatly enriched the form of quantum communication.At present,the theoretical research of controlled quantum dialogues and quantum conferences is mostly limited to lossless and noiseless ideal channels.In the actual communication process,the inevitable existence of quantum channel noise will inevitably affect the quality and safety of communication,and even cause serious consequences.In response to the above problems,this paper studies the controlled quantum dialogue protocols and the quantum conference protocols that can effectively resist noise and have higher security based on different logical entangled states:1.Based on logical χ-type states,this paper designs two controlled quantum dialogue protocols that are resistant to collective-dephasing noise and collective-rotation noise respectively.After obtaining the permission of the controller,the two participants can realize the secure exchange of secret information based on the entanglement relationship of χ-type states with the help of classical information.The existing controlled quantum dialogue protocols face various types of attacks that seriously threaten their security.Among them,the conspiring attacks will invalidate the role of the controller,and the DIS attack and the Do S attack launched by the dishonest controller will give them the opportunities to steal the secret information or interfere with both participants’ communications.These protocols cleverly use logical unitary transformation and the security detection of the controller to achieve the high security of the protocol.Secondly,these protocols use the χ-type states as the quantum resources.Compared with the entangled states used in the similar protocols,it is a genuine four-photon entangled state,which has better entanglement characteristics and is more difficult to be destroyed.In addition,based on the product states which is simple and easy to realize and the superposition states,these protocols use the logic unitary transformation to design the preparation scheme for two types of logical χ-type states that resist collective noise and the corresponding quantum circuits,and focus on the theoretical and implementation of the controlled quantum dialogue protocols,which provide theoretical support for the subsequent laboratory practical preparation.2.Based on the logical Brown states,this paper proposes two controlled quantum dialogue protocols that are resistant to collective-dephasing noise and collective-rotation noise respectively.The controlled quantum dialogue protocols designed using different quantum resources as carriers will provide more options for the practicality of protocols in the future.The Brown state used in these protocols is a five-particle maximum entangled state,which has a strong anti-qubit loss property.That is,after tracing any one of the particles in the entangled state,the remaining four particles are still entangled.The degree of entanglement is better than the maximum entanglement of 2,3,and 4 particles.ensuring that the protocol is free from threats of various attacks and has high security.Meanwhile,because the preparation of the five-particle Brown state is more difficult than the four-particle entangled state,in order to promote its laboratory preparation process,these protocols use the product states which is simple and easy to implement and the superposition states to theoretically prepare the logical Brown state and give the corresponding quantum circuit diagram,which lay the foundation for the practical application of the protocols.3.Based on channel encryption,this paper constructs the three-party authenticated quantum conference protocols under two types of collective noise environments,and extends them to the multi-party authenticated quantum conference protocols.These protocols borrow the excellent ideas of the classic cryptosystem,and use two hash functions to assist in verifying the authenticity of participants’ identity and the integrity and authenticity of secret information.At present,as far as the existing quantum conference protocols are concerned,they are more similar to the quantum broadcast communication in essence,and cannot highlight the interactive characteristics of the conferences well.The quantum conference protocols proposed in this paper have real interactive characteristics of conference,which allows participants to perform multiple rounds exchange of information under the condition of sharing channel resources only once,effectively reducing the loss of quantum resources in multi-round communication.In addition,the security analysis proves that these protocols have high security and can effectively resist various types of attacks that may exist in quantum conference protocols,especially special entanglement attacks.