Monopole Antenna Probe for Density Measurements in Cold Plasmas

A simple diagnostic tool for density measurements in plasma with a certain spatial resolution is proposed in this paper. It uses the emission characteristics of monopole antenna to determine the dielectic property of plasma c = 1 - fp^2/f^2, with the fp electron plasma frequency related to plasma de...

Full description

Saved in:
Bibliographic Details
Published inPlasma science & technology Vol. 13; no. 2; pp. 197 - 200
Main Author 王慧慧 李弘 王雨后 李斌 尤玮 陈志鹏 谢锦林 刘万东
Format Journal Article
LanguageEnglish
Published IOP Publishing 01.04.2011
Subjects
Langmuir
冷等离子体
单极天线
密度测量
探头
等离子体密度
等离子体电位
等离子体频率
Online AccessGet full text

Cover

More Information
Summary:A simple diagnostic tool for density measurements in plasma with a certain spatial resolution is proposed in this paper. It uses the emission characteristics of monopole antenna to determine the dielectic property of plasma c = 1 - fp^2/f^2, with the fp electron plasma frequency related to plasma density. We immersed a inonopole antenna probe into plasma and introduced a microwave signal via a network analyzer. When the emitted power is maximized, the reflected power is minimized and there occurs a resonance. Since can be derived from the resonant frequency, this is actually a method to measure the absolute electron density. Validated by a comparison with the amended Langmuir double-probe method, the monopole antenna probe is valuable. In addition, it is free from the difficulties, such as fluctuation in plasma potential.
Bibliography:WANG Huihui, LI Hong, WANG Yuhou, LI Bin ,YOU Wei, CHEN Zhipeng, XIE Jinlin, LIU Wandong（ CAS Key Laboratory of Basic Plasma Physics, Department of Modern Physics University of Science and Technology of China, Hefei 230026, China）
A simple diagnostic tool for density measurements in plasma with a certain spatial resolution is proposed in this paper. It uses the emission characteristics of monopole antenna to determine the dielectic property of plasma c = 1 - fp^2/f^2, with the fp electron plasma frequency related to plasma density. We immersed a inonopole antenna probe into plasma and introduced a microwave signal via a network analyzer. When the emitted power is maximized, the reflected power is minimized and there occurs a resonance. Since can be derived from the resonant frequency, this is actually a method to measure the absolute electron density. Validated by a comparison with the amended Langmuir double-probe method, the monopole antenna probe is valuable. In addition, it is free from the difficulties, such as fluctuation in plasma potential.
34-1187/TL
electron density, monopole antenna probe, Langmuir double probe, relativepermittivity, resonance frequency
ISSN:1009-0630
DOI:10.1088/1009-0630/13/2/14