Pulsed evaporator of an electrodynamic disperse suspension of particles

Abstract

The action of an electric discharge on various sub stances is one of the methods for obtaining optical media for applied and research purposes. For instance, metal vapors (active media for many lasers) can be obtained by evaporating metals (or substances con taining them) by an electric discharge. The develop ment of gas lasers on vapors of chemical elements necessitates the search for methods of producing high concentrations of atoms of the working substance in a discharge tube since the specific energy output of such lasers is proportional as a rule to this concentration up to rather high values. The use of substances in the form of suspensions sharply increases the efficiency of energy input, which makes it possible to attain high concentrations of vapor up to 10 18 cm -3 [1]. For this reason, electrodynamic disperse (EDD) medium lasers in which the concentration of metal vapors is ensured by evaporation of an EDD suspension of par ticles by a pulsed electric discharge are of considerable interest [2].Considerable attention has been paid in recent years to analysis of two and three level quantum sys tems in the resonant interaction with coherent radia tion. The interest in such investigations is due to diver sity of nonlinear optical processes occurring as a result of nonlinear interference effects. Owing to their cer tain advantages (large oscillator strengths of resonant transitions, closeness of eigenfrequencies to the gener ation frequencies of high power lasers, and relative simplicity of designing), alkali metal vapors are conve nient media for such research works. We are mainly speaking of light volatile Na and K vapors. The reso nant media of Pb and Ba vapors are also of interest. In spite of the long period of investigations, the nonlinear effects emerging in the atomic system under the action of a strong field of resonance frequency have not been analyzed comprehensively. A theoretical model that would fully describe the processes of such an interac tion has not been constructed [3]. For this reason, the obtaining of new resonant media of pure metal vapors with a high concentration is a topical problem for fur ther analysis of nonlinear effects; this problem can also be solved effectively by evaporating an EDD suspen sion.However, not only evaporation of metals by an electric discharge is of interest. The technique described above makes it possible to obtain suspen sions of dielectrics also. During the interaction of dielectric substances with a discharge, chemical reac tion can take place, as a result of which the substances can be decomposed or new compounds can be formed. For example, when the electric discharge passes through a suspension of graphite particles, fullerenes free of oxygen can be formed. In addition, it is possible to obtain metal vapors from their dielectric com pounds; in an electric discharge, it is possible to obtain from Cu 2 O the copper vapor which in turn can serve as an active medium.In this communication, we consider an original technique for obtaining an EDD suspension of...