Abstract
By using an algebraic dynamical approach, the atom-field bipartite system in mixed state is employed to investigate the influence of intrinsic decoherence and Stark shift on the partial entropy change and the entanglement. It is shown that, quality of the partial entropy is improved significantly by introducing the intrinsic decoherence and(or)Stark shift. In addition, by the concept of the lower bound of the concurrence, the entanglement between the atom and the field under the influences of intrinsic decoherence and Stark shift is also presented. (C) 2011 Elsevier B.V. All rights reserved.