Wideband Waveguide CO₂ Lasers

Abstract

The development¹ of the He:Ne waveguide gas laser and its extension² to small, high pressure, sealed-off waveguide CO² lasers allows us to take advantage of the CO₂ pressure broadened gain bandwidth for mode locking and frequency tuning experiments. As the operating pressure is increased above 10 Torr, the linewidth increases from the 50 MHz Doppler broadening at a rate of ~5.3 MHz/ Torr. At pressures above several hundred Torr, it is clear that tuning ranges in the GHz region are possible and nanosecond mode-locked pulses may be produced. CO₂ lasers with these characteristics have been shown to be useful in laser spectroscopy and are essential for CO₂ laser communications.

The research reported in this paper was sponsored in part by the Air Force Cambridge Research Laboratories and the Advanced Research Projects Agency, monitored by the Office of Naval Research.