The Research On The Manipulation Of Quantum Correlations And Related Problems In Cavity Quantum Electrodynamics System

Quantum information science is a new subject combining quantum mechanics and information science.Its emergence has brought about a new information revolution.The advantages of quantum information come from the unique characteristics of quantum mechanics,which is different from classical mechanics.Therefore,it has incomparable capabilities in information transmission,operation speed and information security,etc.Quantum correlation is the indispensable resource in the execution of quantum information tasks.In addition,in order to effectively process and utilize quantum information,it is also essential for physical systems to have qubit integrability.Among them,the cavity quantum electrodynamics system is one of the most promising hardware carriers due to its early research and rapid development.In this thesis,we investigate the manipulation of quantum correlation and related problems based on cavity quantum electrodynamics system,which mainly includes the following three aspects:Firstly,we explore the influence of Kerr-like medium on quantum coherence and quantum information exchange based on cavity quantum electrodynamics system of phase dissipation in chapter three.It is found that stationary quantum coherence appears when the interaction time is long enough.Furthermore,nonlinear Kerr interaction and dipole-dipole interaction could be used to adjust and improve stationary quantum coherence.In addition,we discuss the influence of the nonlinear Kerr interaction and dipole-dipole interaction on the quantum information exchange and flow by making use of trace distance,which indicates that nonlinear Kerr interaction and dipole-dipole interaction could be used to control quantum information exchange in the system and accelerate the quantum information to flow back to the subsystem of two atoms.Secondly,in chapter four,we investigate the non-classical correlations and quantum state transfer between different nodes based on atom-cavity-fiber system,and the influence of nonlinear Kerr medium on non-classical correlations and quantum state transfer is also discussed.It is found that the nonlinear Kerr interaction can improve the effect of non-classical correlations transfer and increase the fidelity of quantum state transfer,meanwhile prolong the existence time of non-classical correlations and quantum state transfer.In addition,results show that nonlinear Kerr medium can increase the storage time of quantum information on the target atoms by discussing the exchange of quantum information in the system.Finally,we explore the influence of nonlinear Kerr interaction on the dynamics distribution of quantum coherence in chapter five.By comparing the research results of quantum coherence and quantum entanglement,we find that quantum coherence still exists when quantum entanglement is zero,which means that quantum coherence may be a more fundamental quantum correlation than quantum entanglement.In addition,it is found that the amount of quantum coherence between two atoms increases with the increase of the strength of the nonlinear Kerr interaction.Finally,the quantum information exchange is investigated by a witness trace distance in the system.It is shown that the Kerr interaction can suppress the quantum information exchange of the system,so as to protect the initial quantum information and quantum properties between two atoms.