Gas discharge powered by the focused beam of the high-intensive electromagnetic waves of the terahertz frequency band

Abstract

The study of the gas discharge in quasioptical beams of electromagnetic radiation of the terahertz (THz) frequency band is attractive for fundamental and applied research. The study of this discharge was made possible by the emergence of unique and reliable sources of radiation of the THz frequency band. Electrovacuum radiation sources of THz band (gyrotrons) have been created at the Institute of Applied Physics (IAP RAS) (Nizhny Novgorod) with a power order of 100 kW in pulsed mode of operation (pulse duration ~ several dozens of µs) and a kilowatt in continuous mode, and investigations of gas discharge phenomena in various gases have been started. Even the first experimental studies of the discharge in noble gases (argon) showed a significant difference in the THz discharge from the discharge at lower frequencies, even in the dynamics of discharge glow. The maximum of the discharge glow was observed after the end of the THz pulse and the afterglow duration was hundreds of microseconds. This paper is devoted to the theoretical and experimental study of the breakdown thresholds of various gases by radiation at 263 and 670 GHz and the study of discharge dynamics in noble and molecular gases under the action of 670 GHz radiation.

Observation of a comb-shaped filamentary plasma array under subcritical condition in 303-GHz millimetre-wave air discharge

“…Relatively few studies have investigated the SC condition. Time-integrated images obtained at 86 GHz in air 17 , 170 GHz in air 18 , 550 GHz in inert gases and nitrogen 19 , and 670 GHz in inert gases and nitrogen 6 showed self-organized filaments. However the discharge structure was not the λ/4 structure.…”

“…Gas breakdown generated by a millimetre-wave beam has been widely studied for applications including beamed energy propulsion 1,2 , communication technology 3,4 , and ultraviolet (UV) radiation sources 5,6 . Gyrotrons are generally used as a high-power millimetre-wave source to ignite plasma 7,8 .…”

Experimental investigation of ionization front propagating in a 28 GHz gyrotron beam: Observation of plasma structure and spectroscopic measurement of gas temperature

“…Atmospheric millimeter-wave discharge may be useful as an ultraviolet light source, 3,4 for detection of radioactive materials, 5 for chemical decomposition, 6 and for beamed energy propulsion. [7][8][9][10][11][12] In propulsion applications, millimeter-wave energy is converted efficiently to gas pressure through the atmospheric discharge.…”

Особенности Пробоя Тяжелых Инертных Газов В Сфокусированном Пучке Излучения Новосибирского Лазера На Свободных Электронах

“…Детальное изучение пробойных явлений в этой работе не проводилось. Пороги пробоя тяжелых инертных газов THz-излучением измерялись в работах [9,10]. При этом отмечалось хорошее согласие экспериментов с результатами расчетов согласно модели пробоя тяжелых инертных газов, представленной в [11] для низких давлений.…”