The influence of phase correlations of components on the energy and polarization parameters of output radiation have been calculated within the framework of the formalism of polarization components. It is shown that these correlations have a marked effect only on the energy characteristics. At the same time, an analysis of the polarization characteristics of a probe wave provides rich information for the analysis of the phase-polarization structure of radiation. An analysis of experimental data allows the inference that the correlation of components is relatively weak even for lasers with a high-Q resonator and at a high excess of threshold values.
Introduction.In a series of works [1-4], a new generalized approach to the description of formation of polarized radiation in a dye-solution laser was suggested and developed. It is based on the representation of laser radiation in the form of a superposition of polarized components, the polarization vectors of which encompass the entire set of possible polarization states. Based on the method of polarization components, a number of characteristic features in the dependences of the energy, polarization, and statistical characteristics of a dye-solution laser near the lasing threshold have been explained.The calculations [2-4] were based on the assumption of statistical independence of the polarization components, which is quite explicable from the viewpoint of the physical mechanism underlying the start-up of the process of lasing as a successive strengthening of spontaneous emission. It was assumed that the statistical independence of polarization components may be considered as the first approximation, and in the process of lasing build-up the phase correlation of polarization components may arise (spontaneously or as a result of any induced processes) and successively become stronger because of the presence of strong feedbacks. Strictly speaking, the method of polarization modes [5, 6], which rather adequately describes the characteristic features of the emission of polarized dye-solution laser radiation upon substantial excess over the threshold, is based on the assumption that the state of radiation polarization can generally be elliptic, i.e., the phase of a light wave is quite a definite one. In other words, the polarization modes are "pure" orthogonal states, the superposition of which completely describes polarized laser radiation.From the viewpoint of the adequacy of this approach, of certain interest are the results of [7,8], in which a change in the polarization of a scanning wave passing through the couvette of a dye-solution laser pumped by a highpower linearly polarized radiation was investigated. Actually, these experiments to a certain extent repeat the classical scheme of nonlinear polarization spectroscopy [9], and, to interpret the results, the basic elements of the corresponding theory of [10] were used: on excitation by a linearly polarized radiation, an orientational anisotropy is created in a molecular medium, and a scanning linearly polarized w...
