Activation and deactivation rates in high-power lasers

A detailed knowledge of activation and deactivation rates for excited molecular states is essential to the design of molecular lasers and their development into efficient high-power devices. This is particularly true when one is attempting to devise new systems, based possibly on molecular electronic transitions in the visible or ultraviolet regions of the spectrum. A table is presented which lists a few such systems. The paper considers some of the mechanisms for production and relaxation of the energy levels involved in these lasers. The discussion covers pumping reactions, deactivation rates (vibrational deactivation, electronic deactivation), as well as information theory and macroscopic relaxation. It is seen that information theoretical methods can be of great value in systematizing and even predicting inelastic collision rates. An even more important application may be to the direct computation of the quantities of importance to laser operation, viz., the population evolution in time.