Waveguide CO/sub 2/ laser gain: dependence on gas kinetic and discharge properties

Technical Report · Mon Sep 01 04:00:00 EDT 1975

OSTI ID:7251457

Cohen, S C

Using a simple rate equation approach the gas kinetic and discharge properties of waveguide CO/sub 2/ lasers were examined. The dependence was calculated of the population inversion and laser small signal gain on gas pressure, gas mixture, pumping rate (discharge current), tube bore diameter, and wall temperature. At higher pressures the gain is optimized by using more helium rich mixtures and smaller bore diameters. The dependence of laser tunability on the gas kinetic properties and cavity losses was determined, it was found that for loss cavities the laser tunability may substantially exceed the molecular fullwidth at half maximum. The more helium rich gas mixtures give greater tunability when cavity losses are small and less tunability when cavity losses are large. The role of the various gases in the waveguide CO/sub 2/ laser is the same as that in conventional devices, by contrast with conventional lasers, the waveguide laser transition is homogeneously broadened. The dependence of gain on gas pressure and other kinetic and discharge properties differs substantially from that predicted by scaling results from conventional low pressure lasers.

• OSTI ID: 7251457
• Report Number(s): N-75-33386; NASA-TM-X-70996; X-723-75-249
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
CARBON DIOXIDE LASERS
ELECTRIC DISCHARGES
GAIN
GAS LASERS
LASERS
POPULATION INVERSION