Temperature dependence of quasi-three level laser transition for long pulse Nd:YAG laser

The influence of temperature and pumping energy on stimulated emission cross section and the laser output of quasi-three level laser transition are reported. Flashlamp is used to pump Nd:YAG laser rod. Distilled water is mixed with ethylene glycol to vary the temperature of the cooling system between −30 and 60 °C. The capacitor voltage of flashlamp driver is verified to manipulate the input energy within the range of 10–70 J. The line of interest in quasi-three level laser comprised of 938.5 and 946 nm. The stimulated emission cross section of both lines is found to be inversely proportional to the temperature but directly proportional to the input energy. This is attributed from thermal broadening effect. The changes of stimulated emission cross section and the output laser with respect to the temperature and input energy on line 946 nm are realized to be more dominant in comparison to 938.5 nm.

► The stimulated emission cross section was studied on quasi-three level laser.
► The lines of interest in this study are 938.5 and 946 nm.
► The study is conducted with respect to temperature and input energy.
► Use of flashlamp to pump the quasi-three level laser.