Theoretical description of discharge plasma and calculation of maximum output intensity of He-Ne waveguide lasers as a function of discharge tube radius

This paper deals with the properties of He-Ne waveguide lasers. An improved theory of the positive column is presented which assumes that at low currents, wall charges restrict the column to a narrow plasma channel and cause the electron temperature to rise. This theory is tested by comparison of measured and calculated current-voltage characteristics and shows good qualitative agreement. Taking into consideration the wall sheath at small currents, the output intensity is calculated. It turns out that an optimum tube radius, mm, exists at which the output intensity has its maximum.