Polarization of radiation of distributed-feedback dye lasers with one- and two-component gain media

Polarization of the radiation generated by a distributed-feedback laser on one-component solutions and binary mixtures of coumarin dyes is investigated. It is established that, with a marked excess of the generation threshold, the degree of polarization P of the radiation generated by one-component solutions is practically independent of the wavelength. For binary mixtures, the spectral behavior of P depends on the donorlacceptor concentration ratio. Here, with the anisotropy of the distribution of excited molecules being partially disrupted in the process of energy transfer (from the donor to the acceptor), the degree of polarization decreases appreciably when radiation frequency is tuned from the short-wavelength region to the long-wavelength one. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 340–343, May–June, 2000.