The POPOP dye vapor laser

We report a comprehensive study of the operation of a laser using the organic scintillator dye POPOP in the vapor phase. Laser operating parameters have been determined, and we describe tuning experiments which demonstrate an oscillation range of 25 nm. Gain measurements as a function of wavelength and time are reported for transverse pumping with the 337.1-nm output of a pulsed N2laser. The quantum efficiency has been measured as a function of temperature and pump wavelength, and a preliminary study has been made of the effect of buffer gases on the quantum efficiency and the gain. Spectral condensation measurements show 90 percent of the broad-band laser output can be obtained in a 1-nm band-indicating that even in a dilute vapor, the thermalization time of the laser levels is ns. We conclude by discussing the implications of these results for the achievement of an electrically pumped dye vapor laser.