Coherently pumped two-frequency laser-type devices

Coherent two-photon pumping of a device in which resonant cavity-modes are coupled to both intermediate transitions of a large number of three level systems is studied further than has been done previously. The dynamics of the three-level system under the influence of two-photon pumping without cavity coupling is shown to exhibit not only spin - 1/2 behavior - the main result of previous investigation - but also spin - 1 behavior. The former occurs for detuning from exact two-photon resonance toward the more strongly coupled intermediate frequency and weak pumping, while the latter occurs for detuning from exact two-photon resonance toward the more weakly coupled intermediate frequency and strong pumping. It is also found that, for certain initial conditions, the level populations remain constant, and no population transfer between levels can be produced by the pumping field.