WA4--Intracavity breakdown in CO and CO2lasers

Author

Rockwood, S.D. ; Canavan, G.H. ; Proctor, W.A.

Author_Institution

Los Alamos Scientific Laboratory, University of California, Los Alamos, NM

Volume

9

Issue

1

fYear

1973

fDate

1/1/1973 12:00:00 AM

Firstpage

154

Lastpage

157

Abstract

The threshold for intracavity breakdown in large CO and CO2lasers has been calculated from solutions for the electron-energy distribution function as a function of incident laser flux. For fluxes of high intensity and short duration, a threshold fluence of $ft_{p} = 1$ J/cm²for He/N2/CO2mixtures and $ft_{p} \\approx 4$ J/cm²for He/CO is predicted. For breakdown at lower fluxes with pulses $t_{p} \\gg 10^{-9}$ s, the threshold becomes flux dependent with values of fcwbetween $4 \\times 10^{8} - 10^{9}$ W/cm²for typical He/N2/CO2mixtures and $f_{cw} \\sim 5 \\times 10^{9}$ W/cm²for He/CO mixtures. Breakdown by pulses traversing laser-amplifier stages is also investigated using both the rate equation and coherent propagation formulation of the problem. It is found that in most cases of interest, breakdown occurs in the short-pulse regime and the coherent solution for the temporal structure is required.

Keywords

Distribution functions; Electric breakdown; Equations; Free electron lasers; Ionization; Laser excitation; Optical propagation; Optical pulses; Pulse amplifiers;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.1973.1077310

Filename

1077310