GENERATION THRESHOLD IN MULTILAYER LASERS

The multilayer laser effect with alternating active and passive layers placed in the Fabry-Perot resonator is studied. The dependence of the generation threshold on the thicknesses of the layers and the refract ive index modulation is described. We show that for the number of acti ve layers N large enough, the minimum threshold amplification follows the rule 1/N-3. To decrease the number of active layers necessary for light generation we can either increase the thickness of the active la yers or decrease the refractive index of the passive layers. The effec t of both is demonstrated.