Development of a Complex for Microwave Diagnostics of Low-Temperature Atmospheric Plasma Jets

Abstract

A system for microwave diagnostics of stationary and non-stationary atmospheric plasma jets has been developed, which is based on microwave cavity resonance spectroscopy. The developed system consists of a spectrum analyzer and a variable length cylindrical microwave cavity resonator, in which the TE111 mode is the main one in the frequency range 1-1.5 GHz. Unlike other modes, the TE111 mode has the highest Q-factor, which makes it the most useful for measurements. By registering the change in the Q-factor of this mode, the parameters of the barrier discharge plasma jet were defined by using perturbation theory. To reduce the influence of the effect of polarization degeneracy of the eigenmodes of the cylindrical resonator, a thin wire was installed inside it in a certain position. To study the dynamics of the plasma jet, a power supply with a pulse modulator was used.