E-beam sustained plasma as a medium for the amplification of electromagnetic radiation in the subterahertz frequency band

It is demonstrated that low-temperature weakly-ionized nonequilibrium plasma created by a high-energy electron beam in gases (gas mixtures) with the Ramsauer minimum in a transport cross section and the effective attachment of slow electrons can be used as a medium for the amplification of electromagnetic radiation in the subterahertz frequency band. An analysis of the electron energy distribution function (EEDF) in a Xe : F₂ mixture is performed. An energy interval with a growing EEDF is found to exist in such a mixture. Such an interval provides the existence of the population inversion of the electron spectrum in the continuum and is responsible for the positive value of a gain factor for microwave radiation. A gain factor depending on amplified radiation frequency and plasma parameters is analysed. (paper)