  An exact solution of the problem of two-atom one- and two-mode
Jaynes-Cummings model with intensity-dependent coupling is presented.
Asymptotic solutions for system state vectors are obtained in the approximation
of large initial coherent fields. The atom-field entanglement is investigated
on the basis of the reduced atomic entropy dynamics. The possibility of the
system being initially in a pure disentangled state to revive into this state
during the evolution process for both models is shown. Conditions and times of
disentanglement are derived.
