Researches About Photon Blockade Based On Four-wave Mixing Effect

With the rapid development of quantum physics and information science,quantum information,as an interdisciplinary subject,has a profound influence on the research of contemporary science and technology.At the same time,quantum communication technology also plays a great role in politics,economy,education and other aspects.Among them,the single photon source is a key factor in the field of quantum information and communication technology.Therefore,how to obtain a single photon source is one of the research hotspots in modern quantum optics.Currently,there are many methods in theory and experiments to obtain single photon sources.For example,the single-atom method and the laser attenuation method,etc.Usually,single photon sources can be effectively realized by a system that produces sub-Poisson light driven by classical light.The physical mechanism behind this approach is the non-classical anti-bunching effect,photon blockade.Single photon sources can be obtained on demand by nonlinear optics effect,which lays a solid foundation for research in the fields of quantum information processing and quantum devices.Currently,there are many systems that can implement photon blockade effect.For example,photon blockade can be produced in circuit quantum electrodynamics system,semiconductor micro-cavity with second-order nonlinear materials,optical cavity with quantum dots,coupled single-mode cavity with third-order non-linearity and photonic crystals.In this thesis,conventional photon blockade effect in the system based on the fourwave mixing effect is analyzed,and conventional photon blockade effect in the four-wave mixing system with Kerr non-linearity is studied.Firstly,by analyzing the energy level of the system,the optimal condition of strong photon anti-bunching is calculated analytically,which proves that the system can realize photon blockade.Next,further numerical calculation could be obtained the expression of the second-order correlation function by solving the master equation,and then the numerical simulation method is used to verify the analytical results.Finally,the numerical results and the optimal blockade conditions analyzed previously are agreed well with each other,which proves that the system studied can realize the photon blockade effect.In order to make the system better realize the photon blockade,the various parameters in the system are discussed in detail,and the influence of the parameters on the single photon source of the system is analyzed,so as to guide the possibility of implementation in the experiment.To further verify the advantages of implementing the current photon blockade Kerr media in four-wave mixing system,we compare the results obtained in the current system with the corresponding results in the four-wave mixing system without filling the Kerr nonlinear media.In this thesis,our studies provide a new theoretical basis for the experimental realization and an availability reference for using the nonlinear four-wave mixing system as a device to generate a single photon source.