Electron energy distributions, transport coefficients and electron excitation rates for RF excited CO2lasers

Publisher Website
Google Scholar
Abstract
The Boltzmann transport equation has been developed for conditions typical of electrical discharges as found in CO2 lasers excited by a rapidly time-varying field. This has then been solved numerically using cross-section data available in the literature. Curves are presented of electron energy distributions, electron drift velocities, diffusion coefficients mobilities and molecular excitation rates for E/N values ranging from 2.0*10-16 V cm2 to 1.0*10-15 V cm2. It is demonstrated that the electron energy distribution over the frequency range relevant to RE discharge excited CO2 lasers (i.e. approximately 20 to 400 MHz) is almost identical to that for DC excitation at the same value of E/N. Factors influencing the onset of frequency effects are examined and their influence on the electron energy distribution discussed. It is also shown how the values of frequency at which the electron energy distribution becomes significantly altered can be estimated.