Entropy Squeezing And Entanglement In The System Of The Atom Interacting With The Field

In the quantum optics field, the study of the quantum properties in the system of the atom interacting with the field has been devoted to considerable attention. It is one of the important contents for the quantum optics to study of the dynamics and non-classical properties of the atom interacting with the field. In this paper, the information entropy squeezing of the atom in the Raman interaction system of an atom interacting with a two-mode field, the quantum entanglement in the system of two atoms interacting with a single-mode field are studied, and many significant results have been obtained.In chapter 1, at first, a simple history overview is presented for the atomic information entropy squeezing and the quantum entanglement in the system of the atom interacting with the field, then the theories of the atomic squeezing and quantum entanglement are explicated. Especially, the atomic information entropy squeezing, the reduced entropy entanglement and the relative entropy entanglement, which form the theoretical basic of the works in the following chapters, are discussed in detail.In chapter 2, the dynamics of the information entropy squeezing of the atomic dipoles in Raman transition model is investigated. The influences of the atomic coherence, the average photon number and the relative phases of the field on the in-formation entropy squeezing of the atom are investigated. The results show that the squeezed component number and the direction of the information entropy squeezing of the atom depend on the coherence of the atom and the relative phases of the field, respectively, and the deep degree of the information entropy squeezing is controlled by the average photon number of the two-mode coherent field. Comparing the results obtained from the atomic squeezing definition based on the Heisenberg uncertainty relation (HUR) with those based on the inforihation entropy uncertainty relation (EUR), the triviality of the atomic squeezing definition based on the HUR is revealed, the information entropy squeezing is a precision measure for the atomic squeezing is shown.In chapter 3, the properties of the quantum entanglement in the system of two two-level atoms interacting with a single-mode coherent field. The quantum entanglement between the two atoms and the field is studied by using the quantum reduced entropy; the quantum entanglement between the two atoms is studied by using the quantum relative entropy; the influences of the atomic dipole-dipole interaction and the average photon number of the coherent field on the degree of entanglement is discussed. The results show that the evolution of the degree of entanglement between the two atom and the field is just the opposite to that of the degree of entanglement between the two atoms, that is, the entanglement between the two atom and the field can impair the entanglement between the two atoms. The properties of the quantum entanglement in the system rely on the atomic dipole-dipole interaction and the average photon number of the coherent field. An increasing in the atomic dipole-dipole interaction intensity leads to the periodic evolution of entanglement and the reduction of the degree of entanglement in the system; an increasing in the average photon number of the single-mode field results in a prolongation of the evolution periodicity of entanglement dynamics and an increase of the degree of...