N-LEVEL ATOM INTERACTING WITH SINGLE-MODE RADIATION-FIELD - AN EXACTLY SOLVABLE MODEL WITH MULTIPHOTON TRANSITIONS AND INTENSITY-DEPENDENT COUPLING

We study the dynamics of an N-level atom coupled in a lossless cavity to a single-mode near-resonant quantized field. The atomic levels are coupled by the multiphoton transitions and the coupling constants between the field and the atomic levels are supposed to be intensity dependent. We find the exact solution for the state vector describing the dynamics of the atom-plus-field system. As an illustration we use the model for studying (i) the time evolution of the atomic occupation probability with the initially coherent field and (ii) the light squeezing, when the cavity field is initially in the vacuum state and the atom is prepared in the atomic `coherent state' (a superposition of atomic states). © 1990 Taylor & Francis Group, LLC.