ENTROPY EVOLUTION OF THE BIMODAL FIELD INTERACTING WITH AN EFFECTIVE 2-LEVEL ATOM VIA THE RAMAN TRANSITION

The properties of entropy evolution of the bimodal field interacting w ith an effective two-level atom via the Raman transition are studied. The influences of the initial average photon number and of the atomic coherence on the evolution of the bimodal field entropy are examined. It is shown that the bimodal field is in a pure state only under certa in conditions in the early stages of time evolution and later tends to a statistical mixture state with maximum entropy values; the bimodal field remains strongly entangled with the atom.