Preparation And Analysis Of Entangled States Based On Weakly Crossed Kerr Nonlinearity

The quantum entangled state is widely used in quantum informatics.The quantum entangled state can be seen everywhere in quantum communication or quantum computing.In quantum communication,quantum teleportation is the entangled state to realize the transmission of quantum information.And quantum encryption communication has proven to be the most secure encryption method.In quantum computers,the ability to compute multiple quantum states in parallel is several orders of magnitude faster than classical computer computing.However,the preparation of quantum entangled states is complicated.How to improve the preparation efficiency? Under the model of linear optics,the efficiency of quantum information processing is relatively low and the wiring is complicated.With the help of coherent states,the cross-Kerr nonlinearity can establish the interaction between photons,thus bringing new ideas to quantum information handling.This paper first introduces a quantum information processing scheme based on weakly cross-Kerr nonlinearity,mainly the preparation scheme of some entangled states,Secondly,the preparation and analysis of C-GHZ states based on weakly cross Kerr nonlinearity are introduced.In the quantum communication of noise environment,the C-GHZ(concatenated GHZ)state is more advantageous than the multi-particle GHZ state because of its robustness and anti-reverse coherence ability.In order to solve the complex problem of C-GHZ state preparation,an improved scheme based on weak cross Kerr nonlinearity to generate C-GHZ state is proposed.Combining homodyne detection technology and classical pre-feedback function,the production process is simplified and almost deterministic realization of the preparation of the C-GHZ state,and a summary of the preparation rules and analysis of the preparation success rate.The improved scheme proposed in this paper uses the packaged optical component module and HWP22.5° half-wave plate.After repeated operation,the nm-GHZ state is derived from the simple C-GHZ state,and finally the C-GHZ state preparation law is obtained.The required number of auxiliary single photons is nm,the number of modules is nm-1,and the number of half-wave plates of HWP 22.5° is n.The success rate simulation and feasibility analysis are carried out.The analysis shows that increasing the amplitude intensity of the coherent state ? and reducing the loss of photon transmission can improve the success rate of C-GHZ state preparation.