The spatial variation of gain and saturation is analyzed in weakly and heavily saturated cases for a fast axial flow (FAF) CO2 laser amplifier with laser gas in laminar and turbulent flow regions. Expressiong the laser parameters by fourth-order even functions of the radial distance, the development of the amplified radiation is predicted and compared successfully to the experimental results for the 10P(18) line. The distinctive feature of a FAF system is enhancement of the gain and saturation irradiance as well as the mode volume. The condition of spatial soliton is also discussed in a heavily saturated case.
© 1989 Optical Society of America
Original Manuscript: March 6, 1989
Published: September 1, 1989
Nobuaki Takahashi, Eiichi Tsuchida, and Heihachi Sato, "Spatial variation of gain and saturation in a fast axial flow CO2 laser amplifier," Appl. Opt. 28, 3725-3736 (1989)