Output power of a laser utilizing multistage transitions

The problem of the output power of a laser utilizing multistage (cascade) transitions is solved using a model of a nonbranching cascade. It is shown that the multistage nature of the transitions results in a completely different distribution of the output power between the transition lines of a cascade than would follow from estimates of the unsaturated population inversion and losses. In the case of a cascade of transitions with similar parameters the distribution of the power between the lines (considered as a function of the line number) is approximately quadratic with a maximum at the center of the cascade, whereas the integrated power is proportional to the cube of the cascade "length"