Transmission characteristics of microwave in a glow-discharge dusty plasma

Abstract

In this study, the propagation characteristics of electromagnetic wave in a glow discharge plasma with dust particles are experimentally investigated. A helium alternating current glow discharge plasmas have been successfully generated. Measurements of the plasma parameters using Langmuir probes, in the absence of dust particles, provide plasma densities (ne) of 1017 m−3 and electron temperatures (Te) ranging from 2 to 4 eV. Dusty plasmas are made by adding 30 nm radius aluminum oxide (Al2O3) particles into the helium plasma. The density of the dust particle (nd) in the device is about 1011–1012 m−3. The propagation characteristics of electromagnetic waves are determined by a vector network analyzer with 4–6 GHz antennas. An apparent attenuation by the dust is observed, and the measured attenuation data are approximately in accordance with the theoretical calculations. The effects of gas pressure and input power on the propagation are also investigated. Results show that the transmission attenuation increases with the gas pressure and input power, the charged dust particles play a significant role in the microwave attenuation.

Specific Features of Microwave Methods for Dusty Plasma Diagnostics. I. Dielectric Permittivity, Refractive and Absorption Indices

“…In this case, the ionic component in the dielectric permittivity has to be taken into account (see, e.g., Eqs. 7and (8)). Second, in the general case, dust particles are different by their size and are described by a certain distribution function [9,12].…”

“…The active methods are used to measure some parameters in both weakly and strongly ionized plasma (the electron concentration, the collision frequency, and others), as well as in a high-temperature plasma in experiments dealing with controlled thermonuclear fusion. Recently, the application scope of active microwave methods was somewhat extended owing to their usage in the diagnostics of a dusty plasma [5][6][7][8].…”

“…As was already mentioned, the development of microwave methods for the dusty plasma diagnostics has received an impetus in recent years [5][6][7][8]. There are several approaches aimed at the consideration of the interaction between electromagnetic waves and a dusty plasma [23,24].…”

Detection of the Lunar Surface Soil Permittivity with Megahertz Electromagnetic Wave

“…The plasma frequency, , can be calculated from the plasma electron density, , by , where represents the single electron mass. denotes the charging response factor of the dust, which can be obtained as [ 25 , 26 ] where is the radius of dust in the lunar ionosphere; represents the dust density. The dusty particle charging frequency, , and the plasma collisional frequency, , are also important parameters to describe the dusty plasma.…”

Study of Coulomb collisional effects on the propagation of electromagnetic waves in a turbulent plasma

“…A collisional Weibel instability has been investigated by many authors in recent years. [ 16,23–37 ] Stress effect has been neglected in the calculation of the growth rate of the collisional Weibel instability in laser–plasma interaction. The unstable Weibel mode, driven by the anisotropy in the distribution function caused by the heat flow, can have significant growth rates occurring at densities above critical.…”