Interaction of a two-level atom and a field with a time-varying frequency in a Kerr-like medium

The interactions between a two-level atom and a coherent field with a time-varying frequency in a Kerr-like medium have been investigated. It is found that the average of the atomic population inversion is deformed as the frequency changing with time in sine form. It is interesting that when the amplitude of field modulation and third-order nonlinear susceptibility are adjusted to certain values, the collapse–revival phenomena of population inversion in the standard Jaynes–Cumming model disappear and are replaced by a nearly Rabi-oscillation-like evolution. In other words, population inversion in the initial coherent field behaves like that in the initial Fock state. This provides a new way to manipulate the interaction between the atom and the field, and has potential applications in quantum information and quantum communication.