Dye Lasers in the Ultraviolet

Abstract

POTENTIAL applications of dye lasers in the fields of air pollution monitoring, photochemistry and biology have stimulated interest in operating dye lasers in the spectral region below 4500 Å. Many important molecular resonances and reaction thresholds are found at these higher photon energies. Using an AVCO C950 pulsed N₂ gas laser, with its output at 3371 Å in the ultraviolet, we have been able to obtain continuously tunable dye laser action as low as 3550 Å. This pumping technique has been described in some detail elsewhere¹. The present scheme has a transverse pumping configuration where the rectangular N₂ laser beam is focused to a line within the dye cell and the dye laser's optical cavity. The pumping laser is capable of 100 kW peak power in a 10 ns pulse duration, and can be pulsed at rates as high as 100 pulses per second². In the visible region of the spectrum, this system has produced dye laser peak powers as high as 30 kW and repetition rates up to 100 pulses s⁻¹. It is also significant that the visible dyes have attained these repetition rates in sealed dye cells without any external dye circulation.