EFFECT OF THE DIPOLE-DIPOLE INTERACTION ON THE PURE 2-ATOM SQUEEZED STATE

The influence of the dipole-dipole interaction on the final atomic sta te of a two-atom system driven by a coherent laser field and damped by a broad-band squeezed vacuum is discussed. It is shown that in the ab sence of a coherent laser field the final atomic state is independent of the dipole-dipole interaction and can be the pure two-atom squeezed state only if detuning of the squeezed vacuum field from atomic reson ance is equal to zero. In the presence of a coherent laser field, the final atomic state depends on the dipole-dipole interaction. As the la tter increases, the final atomic state shifts from a mixed state to th e pure two-atom squeezed state. However, this happens only if the driv ing field and the squeezed field frequencies are tuned to the atomic t ransition frequency. For the driving field and the squeezed vacuum fie ld frequencies detuned from atomic resonance the system decays into a mixed state irrespective of the dipole-dipole interaction between the atoms.