Nonlinear And Non-Classical Quanlity Of A Three-Level Atom Interacting With Fields

First, the evolution properties of the field entropy of the system of three-level atom interacting with the single-mode coherent-state light field are investigated in this paper. And the evolution rules of the field entropy in the process of a single-mode coherent-state light field interacting with a cascade three-level atom Without Rotating Wave Approximation and with a V-type three-level atom inside a cavity filled with a Kerr medium are studied. The influence of the initial mean photon number n (the initial field directivity), of the virtual light-field effect and of the Kerr effect on the field entropy evolution properties of each model are also discussed respectively. It has been shown that the periodicity of the curves of the field-atom is influence by the initial mean photon number -n . With the increase of the initial field directivity n , the mean value of the evolution curves of the field entropy increase constantly when the initial field directivity n is not big, therefore, the related degree of the field-atom strengthens. And in the condition of strong field, with the increase of the initial field directivity -n , the related degree of the field-atom decreases constantly and disappears. Without Rotating Wave Approximation, the virtual light - field effect leads to the additional vibrations of entropy. With the increase of the initial mean photon number n of the light field the extent of the additional vibrations of entropy increases. And with the increase of the light-field frequency ω, the extent of the additional vibrations of entropy decreases and then disappears. The Kerr medium intensity parameters μ influences the periodicity of the evolution curves of the field-entropy. With the increase of μ, the Rabi oscillation frequency of the evolution curves of the field entropy becomes rapid obviously. But its maximal value decreases constantly.Secondly, the atomic population evolution vs. time in the system of a three-level cascade atom interacting with the single-mode squeezed coherent in a Kerr medium is investigated. And the influence of Kerr medium intensity parameters μ, the squeezed light-field factor y and the coherent vibration amplitude |α|2 of the field -atom on the atomic population is also discussed. It has been shown that the intensity coefficient μ of Kerr medium, the squeezed light field factor γ and the coherent vibration amplitude |α|2 of the light field influence the quantum collapse-revival periodicity of the evolution curves of atomic population directly. And the non-linearity Kerr medium μ can weaken the interaction of the atom with the field. When Kerr medium μ and the interaction of the field-atom increase to a certain value, the correlation degree of light field and atom will weaken and disappear.Finally, the evolution vs. time of the mean photon number and the Mandel factor Q (t) in the system of the single-mode squeezed coherent-state interacting with a V-type three-level atom in the Kerr medium are studied. It has been shown that with the increase of μ, the Rabi oscillation extent of the mean photon number and the Mandel factor Q (t) decrease. Meanwhile, the period of the quantum collapse-revival of two evolution curves shorten. When μ increase to a certain value, the Rabi oscillation disappear, and two evolution curves become a horizontal-line. This shows that the non-linearity interaction of the Kerr medium can weaken the interaction of the field-atom. The period of the quantum collapse-revival of the evolution of and Q (t) of the system is influenced by |α|2 and γ. Meanwhile, two three-dimension evolution curves are the curved-surface of extremum. This shows that the strong field can weaken the non-classical quantum effect of the stimulated radiation field and strengthen the classical effect of the stimulated radiation field because -n= = |α|2 + Sinh2(γ). And the common action of them is equal'to the action of the initial field intensity of the single-mode coherent light field. The coupling parameters of the atom-field influences...