Measure of the characteristics of TEA CO2 amplifier and experimental study of the propagation of a laser pulse with an exponential front in the amplifying media and absorption at 10.6 microns

An experimental evaluation of the performance of two types of double-discharge TEA CO2 amplifiers is presented. The amplifiers are used to study and observe the different characteristics of the propagation of an optical pulse with an exponential leading front in both the linear and saturated amplifying regime. The construction and operation of a Laflamme-type and Seguin-type double-discharge TEA CO2 amplifiers are presented. The small signal gain performance of these devices is compared and evaluated. Operation of these amplifiers in the saturated state allows the determination of the saturation parameter relative to the medium and leads to an evaluation of the radiative cross section of the considered transition. The realization of the single longitudinal mode TEA CO2 laser source is presented. The output pulse of this laser is then propagated in a five-pass amplifier that uses one of the previously described double-discharge devices. Pulse widening and superluminal velocity is observed and determined quantitatively. Finally a two-component medium is formed by a alternating TEA CO2 amplifiers with SF6-He absorbing cells.