Use of a model of coupled microcavities in the interpretation of experiments on powder lasers

The dependence of the lasing frequency of mixtures of activated powders on the pump wavelength is simulated by regarding a lasing powder as an aggregate of active optically coupled microcavities. It is assumed that the components of the powder mixture differ from one another only in respect of the laser transition frequency. A comparison with the experimental results obtained for mixtures of Na₅La_1–zNd_z(MoO₄)₄ (z = 0.15 and 0.95) powders shows that the adopted model yields results close to those obtained experimentally both at the centre and in the wings of the excitation line.