A High Average Power Dye Laser Powered by a Vortex Stabilized Flashlamp

Abstract

A flashlamp pumped organic dye laser has recently been operated at an average power output of 114 W. This is the highest average power ever reported for a dye laser. The laser was excited by a high power, vortex stabilized flashlamp. In this type of lamp a fast flow of argon gas is injected near the walls. The gas swirls inward and exits through holes in the electrodes. The fast gas flow provides cooling to allow the lamp to operate at high average power and it also stabilizes the position of the discharge. The lamp was used in an elliptical pumping cavity, with the lamp at one focus. The arc length in the lamp was 10 cm. The dye was circulated through a transverse flow channel at the other focus. The lamp was fired at repetition rates up to 357 Hz and with an energy per pulse of 211 J, i.e. an average power of 75 kW. The laser output pulses had a full width at half maximum of 1·8 μ sec. The average power output increased nearly linearly with repetition rate to a maximum of 114 W at 255 Hz. The achievement of even higher powers was limited by the replacement rate of dye in the channel and a drop in the flashlamp intensity at higher repetition rates. The dye used in these experiments was Rhodamine 6G in an ethanol solution.