Research On Multi-party Quantum Communication Based On Entanglement Swapping And Hyper Entanglement

Secret sharing is a kind of encryption technology,which divides a secret information into multiple parts and allocates these parts to different participants.Only when a sufficient number of participants gather together,can the original secret information be reconstructed.In practice,secret sharing can be used for data backup,password management,healthcare,and more.Compared with classical secret sharing,quantum secret sharing(QSS)has higher security and non-repudiation,and can effectively solve problems such as eavesdropping and tampering.Therefore,QSS protocol is mainly divided into two parts: the first part is secret sharing,and the second part is multi-party cooperation to recover secrets.In order to resist the attack of eavesdropper on measuring equipment,researchers propose a quantum secret sharing scheme independent of measuring equipment.Most of the existing schemes are more difficult to implement.In addition,quantum key agreement(QKA)is different from QSS.As another branch of quantum communication,it realizes the establishment of a secure secret key between communication participants.Due to high requirements,most of the existing schemes have low communication efficiency,and it is difficult to extend from two to many parties.In order to solve the above problems,we put forward the research of quantum communication schemes based on entanglement switching and hyper-entanglement.The main work is as follows:In the first work,we propose a multi-party measurement-device-independent QSS protocol based on entanglement swapping,which belongs to the part of secret key recovery in quantum secret sharing.The protocol uses a measurement-device-independent technique where all measuring tasks are handed over to an untrusted measuring party so that our protocol is resistant to all possible attacks from imperfect measuring equipment.At the same time,entanglement channel is constructed between two participants by entanglement swapping.Our protocol requires linear Bell state analysis,which is also easy to operate.In the second work,a QKA protocol based on hyper-entanglement is proposed,which utilizes the hyper-entanglement Bell state as a quantum resource and uses the measurement of the hyper-entanglement Bell state as the main operation.The protocol does not require the assistance of a third party,but ensures fairness,security and efficiency.The implementation of the proposed protocol only requires the measurement of hyper-entanglement Bell states and linear hyper-entanglement Bell states.Compared with the previous QKA protocol,this protocol has a higher channel capacity,and each photon pair can transmit 4 bits of information under the complete hyper-entangled Bell state analysis.