  We study the entanglement properties of a pair of two-level atoms going
through a cavity one after another. The initial joint state of two successive
atoms that enter the cavity is unentangled. Interactions mediated by the cavity
photon field result in the final two-atom state being of a mixed entangled
type. We consider the field statistics of the Fock state field, and the thermal
field, respectively, inside the cavity. The entanglement of formation of the
joint two-atom state is calculated for both these cases as a function of the
Rabi-angle $gt$. We present a comparitive study of two-atom entanglement for
low and high mean photon number cases corresponding to the different fields
statistics.
