THE TRANSMISSION OF HIGH-POWER INFRARED PULSES THROUGH $SF_{6}$

Abstract

The transmission of high-power infrared pulses from a Q-switched $CO_{2}$ laser through $SF_{6}$ and $SF_{6}$-buffer gas mixtures has been studied under conditions where coherent effects are negligible. The results indicate that the rotational relaxation rates of the directly pumped levels determine the response of the system under the conditions studied. A four-state model which predicts the saturation behavior of $SF_{6}$ under low-power (less than 100 watts/$cm^{2}$) c-w $irradiation^{1}$ has been adapted for the computation of transmitted pulse shapes. Cross sections for rotation-translation energy transfer can be extracted with the aid of this model. These results have implications for the understanding of passive Q-switching in molecular lasers.