Damage to CdS single crystals by laser's own radiation

Transmission electron microscopy was used in a study of the defect structure and morphology of the damage to CdS crystals by stimulated radiation generated in these crystals on excitation with nitrogen laser (λ = 337 nm) pulses. Platelet CdS crystals of thickness 0.2–0.5 μ were used because this made it possible to carry out transmission electron microscopic studies before and after lasing. The damage was attributed to melting and evaporation because of the development of a thermal instability as a result of the following processes: absorption of the radiation by precipitates, dislocations, and nonequilibrium free carriers; self-focusing; focusing by elastooptic lenses formed by the stress fields of the precipitates.