The field entropy squeezing properties of J-C Model in Two-Photon Processes are studied. The influences of the initial state of atoms and the frequency detuning value on the field entropy squeezing are discussed.
The field entropy squeezing properties in the nonlinear Jaynes-Cummings model are studied by means of quantum information entropy, and the influences of the nonlinear interaction of the Kerr medium with the model field and the initial state of atoms on the field entropy squeezing are discussed. It shows that the nonlinear interaction of the Kerr medium can lead to an increase in the squeezing depth. On the other hand, the squeezing time and the squeezing depth increases with the increase of the atomic distribution angle.
From the quantum information point of view we investigate the entropy squeezing properties of a two_level atom with arbitrary initial state interacting with the coherent field via the two_photon process. The influence of the initial state of the system on the atomic information entropy squeezing is discussed. The numerical results obtained from the uncertainly relation of quantum information entropy are compared with those obtained from the uncertainly relation of Heisenberg. It is shown that the number of squeezed component of the atomic dipole, squeezed frequency, squeezed amplitude and squeezed direction of the atomic information entropy squeezing can be controlled by choosing the initial atomic distribution angle, the atomic mixing degree and the relative phase of the field mode, respectively. Quantum information entropy is a remarkable precise measure for the atomic squeezing.
The information entropy squeezing properties of the atom interacting with the Glauber-Lachs state in multi-photon Jaynes-Cummings model are studied by means of the full quantum theory.The influences of the mean number of the coherent photons,the average number of the thermal photons,the number of the transition photons and the atomic initial state on the information entropy squeezing of the atom are discussed.The results indicate that there is no entropy squeezing in the Xcomponent of information entropy of the atom at any instant of the time evolution of the system.But there exists an entropy squeezing in the Ycomponent of information entropy of the atom during the time evolution when the mean number of coherent photons takes an appropriate value.The mean number of thermal photons and the number of the transition photons have a destructive effect on the Ycomponent of information entropy of the atom.The atomic initial state has no effect on the entropy squeezing in the Ycomponent of information entropy of the atom.If the number of the transition photons equals to two,the time evolution of the entropy squeezing factor appears periodic change.
The atomic entropy squeezing of the Jaynes-Cummings model driven by classical fields in non-Markovian environment is investigated according to the non-Markovian quantum theory and the entropy squeezing theory. Our attention is focused on the influences of the non-Markovian effects, the Rabi frequencys of classical fields and the detuning on the atomic entropy squeezing. And we explain the atomic entropy squeezing dynamic by the memory effects of the non-Markovian processes. It is found that the atomic entropy squeezing can be maintained for a long time when both the Rabi frequencys of classical fields and the non-Markovian effect are present simultaneously. And we can obtain the optimal squeezing states by choosing appropriate parameters of the Rabi frequency and the detuning of classical field. Our results provide a potential method of generating high-degree squeezed and longtime atomic squeezing states by controlling the atom-field interaction.