Influence of the Kerr-Like and the External Classical Field on the Atom-Field Interaction

In this communication we study the interaction between a two-level atom and an electromagnetic field in the presence of the classical field and Kerr-like medium. Under a certain condition the system is transformed to the usual Jaynes-Cummings model. The atomic inversion is investigated where the phenomenon of super-structure is reported for a large value of the classical field coupling parameter. Our results show that the information of variance and entropy squeezing beside the purity can be controlled by both of the coupling parameter of the classical field and the Kerr-like medium parameter

The dynamical effect of stark-shifts produced from a four-level atomic system

We consider a two-mode quantized field described in a coherent state interacting with a four-level atom. An effective Hamiltonian is obtained by adiabatically eliminating the intermediate two levels in a cascade process. The influence of the Stark shifts on the atomic inversion is examined, as well as on the second order auto-correlation function and on the cross-correlation between the field modes. The results of the calculations are illustrated numerically