Investigation of optical inhomogeneities in chemical lasers

An experimental study was made of the changes in the refractive index Δn of the active media of F₂+D₂+He (CO₂, SF₆) chemical lasers during stimulated emission. It was established that 80–90% of the energy was emitted by a laser when the active medium was optically homogeneous (|Δn|≤ 2×10^–7). The change in the refractive index at the end of a stimulated emission pulse did not exceed (0.7–1.5)×10^–6. This change was attributed to gasdynamic motion of the medium because of its nonuniform heating by the chemical reaction.