Influence of pump repetition rate on dye photostability in a solid-state dye laser with a polymeric gain medium

The influence of pump repetition rate on the conversion efficiency and photostability of a polymeric gain material doped with the dye Rh6G is studied. The effect of heating of the host polymeric matrix due to the high pump repetition rate in the stimulation of chemical reactions, leading to dye photodestruction, is discussed. Such heating appears to influence the polymeric gain material photostability considerably. The increase of the diffusion rate of the dye due to weak heat dissipation in the gain material and heating of the gain medium, consequently resulting in the migration of dye molecules from a pumped volume, is reported and discussed for the first time. The role of additives with low molecular weights in the polymeric matrix in increasing the photostability of the polymeric gain material is discussed.