Resonance wave discharge and collisional energy absorption in helicon plasma source

Abstract

The concept of the 'resonance' wave discharge is introduced to explain the high absorption efficiency of inductively coupled helicon plasma source. This discharge is supported by long-scale weakly damped eigenmodes.excited in plasma resonator. The rf power absorbed in it is inversely proportional to electron collision frequency. The fields excited by simple single-loop inner antenna and its impedance are calculated in a cylindrical metal resonator. At low collision frequencies the field amplitudes and antenna resistance are shown to peak sharply near the helicon dispersion branches.

Permanent Magnet Helicon Source for Ion Propulsion

“…The latter are integrated to obtain the plasma loading resistance R p , our principal result. The absorption of RF energy is dominated by mode conversion to heavily damped Trivelpiece-Gould (TG) modes 31 at the radial surface, and this Shamrai 32 effect is fully accounted for in HELIC. Electromagnetic radiation, ion mass effects (such as lower-hybrid resonance), and Landau damping are included, but none of these effects is important in the parameter regime of this paper.…”

Plasma dynamics in a helicon thruster

“…The TG waves are short-wavelength and dissipative and appear usually as surface waves. For given ω and B, there is a ¦nite range of n e where both helicon and TG waves propagate within the plasma column and e©cient energy absorption is achieved [13,14]. This is called the helicon or blue mode in contrast to the inductive mode, when the helicon waves penetrate evanescently within the plasma.…”

Wave mode conversion and mode transition in very high radio frequency helicon plasma

“…[1][2][3][4] Many previous results asserted that the power absorption in the helicon plasma is due to the Trivelpiece-Gould mode ͑TG mode͒. [5][6][7][8] Although many researchers have been trying to explain the mechanisms of efficient power absorption, it has not been clearly examined yet due to difficulties in its detection. 5,9 As the TG mode tends to be localized in a thin surface layer, the direct measurement is too difficult.…”

“…[5][6][7][8] Although many researchers have been trying to explain the mechanisms of efficient power absorption, it has not been clearly examined yet due to difficulties in its detection. 5,9 As the TG mode tends to be localized in a thin surface layer, the direct measurement is too difficult. Due to the difficulty of measurement, almost no experimental evidence for the heating by the TG mode has been reported.…”

“…5 For Ӷ ce , the wave dispersion is separated into two wave modes, namely the helicon mode and the TG mode. They report that those two wave modes merge under a typical condition and that the helicon mode converts to the TG mode.…”