Numerical simulation of the main characteristics of a high-pressure laser for amplification of picosecond laser pulses

Abstract

The gain characteristics of the medium of a pulsed laser in the ten-micron region at the working gas pressures from 1 to , which were experimentally determined in [], are numerically simulated using a scheme that includes the main chemical and relaxation processes. It is shown that the chosen scheme of processes makes it possible (i) to numerically describe the experimental data on the temporal behaviour of gains; (ii) to explain the reason for early degradation of gains (at the degree of transformation of about 20 %); (iii) from comparison of experimental and calculated temporal gain profiles, to determine the degree of photodissociation of molecules, which is an important parameter determining the operation of pulsed chemical lasers; and (iv) to predict the gain characteristics of working mixtures depending on their composition and pressure and on the initiation parameters. The predicted gains in the mixtures of the optimal composition at a pressure of , a degree of dissociation of molecules per flash , and a flash duration at half-width of are .