Quantum Information Transmission Based On Three-Photon GHZ States And W States

A new discipline,quantum informatics,was born in the 1980 s.It is a combination of physics,information,and mathematics.Quantum entanglement is one of the important resources in quantum information,and it plays a key role in quantum information technology.Using quantum entanglement,the system in the entangled states is used as a carrier for transmitting secret information,and the coherent characteristics are used to encode and transmit the secret information.Based on optical systems,more and more quantum communication schemes have been proposed,which has become one of the leading topics in the field of quantum communication.Quantum communication schemes using only linear optical methods have complicated circuits and low success probability,making it difficult to implement information transmission schemes.The application of non-linear optical methods can reduce the complexity of quantum communication circuits and increase the success probability.The main research work of this thesis is to apply weak cross-Kerr nonlinearity media,consider the influence of collective noise,and use entangled photons as secret information carriers to propose a quantum information transmission scheme based on entangled GHZ states and perfect W states.This thesis is divided into four chapters,of which chapters 3 and 4 are our main research work,and the specific content is arranged as follows:The first chapter describes the research background and significance of this thesis,including the establishment of quantum information,the current status and prospects of development.The second chapter briefly introduces the preliminary knowledge related to the research content of this article,including quantum bit,quantum entanglement,optical elements,nonlinear cross-Kerr effect,and classic quantum key distribution protocols.The third chapter studies quantum information transmission using entangled GHZ states.First,using linear optical elements,a fault-tolerant distribution of entangled GHZ states with immune collective noise among the three parties is proposed.Secondly,byapplying single parity analysis and double parity analysis based on weak cross-Kerr nonlinearity,two controlled deterministic secure quantum communication protocols are proposed:One is to apply the idea of single parity analysis and quantum teleportation,without having to completely distinguish between Bell states,and the scheme is simple;the other is to apply the idea of double parity analysis and dense coding,which is efficient.The fourth chapter studies quantum information sharing based on the perfect W stats.The entanglement of the W states is more robust than the entanglement of the GHZ stats.The perfect W state can realize the teleportation of 100% success probability for a single bit arbitrary states.First,a fault-tolerant distribution circuit is applied to distribute fault-tolerantly perfect W states in a collective noise channel.Secondly,using a quantum circuit based on weak cross-Kerr nonlinearity,after completing the splitting of the single quantum bit information,one of the two communicating parties performs two classic feed-forward operations with the cooperation of the other party,to achieve the sharing quantum information of single-qubit.Finally,we give a concluding remarks on the research content of this article.