Research On Properties Of Entanglement In The System Of Trapped Ions Interacting With The Field

Since Cirac and Zolloer first put forward the quantum calculation method based on trapped ion system,theoretical analysis and practical application of quantum information processing based on trapped ion system has made great progress,and the trapped ion system has important application value in the theoretical study on quantum entanglement.Physicists can manipulate and control the internal electronic and the external motional states of trapped ions with the system the trapped ions interacting with the light fields.Recently,the study of entanglement dynamics based on trapped ion system has become a hot research topic.In this paper,we introduce the quantum entanglement theory,the trapped ion system,and study the entanglement dynamics in the system of trapped ion interacting with the field,the main contents are as follows:Using the theory of quantum information and quantum entanglement,the system of interaction between single trapped ion and the standing wave laser field has been studied.The influence of the coupling strength between ion and field,the detuning between ion and field on the entanglement between the ion and its centroid mode is discussed.Getting the conditions for the transfer of ions from the internal state to the vibrational state by the analysis of the Hamiltonian between the ions and the centroid mode under the interaction picture.A system composed of two mutually independent trapped ion systems is studied.The two subsystems are composed of trapped ions and classical fields.The two parts have no any interactions except the initial correlations originating from ions entanglement The properties of entanglement is measured by the concurrence and negativity,the effect of the initial entanglement degree between the two ions on the entanglement of the system is discussed,which is providing a way to manipulate and control the entanglement in theory.Analysis the system of a single two level ion interacting with field,study on the entanglement properties between internal state of the ion,the vibrational state of ionic center of mass in trap and the state of cavity.The effects of the internal states of the ions on the time evolution of the two-body and three-body entanglement in the system are discussed.