Abstract
We consider the effect of damping on a quantum system described by the su(1; 1) Lie algebra and interacting with a two-level atom. We obtain the numerical solution of the associated differential equations and discuss in detail some statistical aspects, atomic population inversion, squeezing phenomena, and negativity. In addition, we analyze the effect of the decay parameter on the population inversion and purity. Finally, we examine entropy squeezing and the degree of entanglement for some values of the damping and detuning parameters.