Properties of field quantum entropy evolution in the Jaynes--Cummings model with initial squeezed coherent states field

The properties of the field quantum entropy evolution in a system of a single-mode squeezed coherent state field interacting with a two-level atom is studied by utilizing the complete quantum theory, and we focus our attention on the discussion of the influences of field squeezing parameter \gamma , atomic distribution angle \theta and coupling strength g between the field and the atom on the properties of the evolution of field quantum entropy. The results obtained from numerical calculation indicate that the amplitude of oscillation of field quantum entropy evolution decreases with the increasing of squeezing parameter \gamma , and that both atomic distribution angle \theta and coupling strength g between the field and the atom can influence the periodicity of field quantum entropy evolution.