COOPERATIVE ATOMIC BEHAVIOR AND OSCILLATOR FORMATION IN A SQUEEZED VACUUM

Time-dependent (numerical) results are presented for super-radiant beh aviour in the Dicke model of N-a=2,3 atoms in a broad band squeezed va cuum. This concerns the fluctuations and the intensity of the fluoresc ent radiation as well as the atomic population inversion of the system with atoms initially in an atomic coherent state. In the steady state , and in the N-a-->infinity, we show that the 'atomic' Dicke model beh aves like a 'giant quantum oscillator', in which the number of excited atoms asymptotically approaches the average number of photons in the resonant mode of the squeezed vacuum, just as in the thermally driven case.