Intrinsic decoherence in non-degenerate two-quanta Jaynes-Cummings model

The non-degenerate two-quanta Jaynes-Cummings model governed by Milburn equ ation is studied. This models the decoherence of a quantum system as it evo lves through intrinsic mechanisms beyond conventional quantum mechanics gov erned by the Schrodinger equation. The exact solution is given. Then it is applied to investigate the effects of the intrinsic decoherence on nonclass ical effects (population inversion, oscillations of the number distribution , photon antibunching effect, the cross correlation and squeezing of the ca vity field). We show how the intrinsic decoherence suppresses the nonclassi cal behaviour in this model, for the off-resonant case.