Measurement of the Complex Conductivity of an Ionized Gas at Microwave Frequencies

Publisher Website
Google Scholar
Abstract
The positive column of a glow discharge is placed along the axis of a cylindrical cavity excited in the TM010 mode. The transmission of 3‐cm waves through the cavity and the shift in resonant frequency are observed as a function of discharge current. It is shown that from these measurements values of the complex conductivity, σr+iσi, of the electron gas can be calculated. Curves of the measured conductivity components as functions of pressure and current are given. Using a theoretical formula for the conductivity (see reference 6) values of electron density can in turn be calculated from both σr and σi. Langmuir probe studies are carried out to check the results obtained, and adequate agreement is found.