Superluminescence and stimulated emission from unstable photoisomers of polymethine dyes

The criteria governing the superluminescence and stimulated emission from unstable photoisomers of polymethine dyes are studied for the first ime. It is shown that this is an important factor in stimulated emission from polymethines under conditions of anti-Stokes pumping of initial stable molecule solutions. Numerical calculations are made of the gain spectra of polymethine solutions containing photoisomers pumped by radiation of varying spectral composition. Conclusions are drawn on the influence of photoisomerization on the stimulated emission characteristics of these media under different pumping conditions.