Effect of antenna helicity on discharge characteristics of helicon plasma under a divergent magnetic field  

作　　者：孙萌 徐晓芳 王陈文 尹贤轶 陈强 张海宝 Meng SUN;Xiaofang XU;Chenwen WANG;Xianyi YIN;Qiang CHEN;Haibao ZHANG(Laboratory of Plasma Physics and Materials,School of Printing and Packaging Engineering,Beijing Institute of Graphic Communication,Beijing 102600,People’s Republic of China)

机构地区：[1]Laboratory of Plasma Physics and Materials,School of Printing and Packaging Engineering,Beijing Institute of Graphic Communication,Beijing 102600,People’s Republic of China

出　　处：《Plasma Science and Technology》2024年第6期50-59,共10页等离子体科学和技术（英文版）

基　　金：supported by the Beijing Municipal Natural Science Foundation (No. 1242015);Discipline Construction of Material Science and Engineering (Nos. 21090122014 and 21090123007)。

摘　　要：The characteristics of the blue core phenomenon observed in a divergent magnetic field helicon plasma are investigated using two different helical antennas, namely right-handed and lefthanded helical antennas. The mode transition, discharge image, spatial profiles of plasma density and electron temperature are diagnosed using a Langmuir probe, a Nikon D90 camera,an intensified charge-coupled device camera and an optical emission spectrometer, respectively.The results demonstrated that the blue core phenomenon appeared in the upstream region of the discharge tube at a fixed magnetic field under both helical antennas. However, it is more likely to appear in a right-handed helical antenna, in which the plasma density and ionization rate of the helicon plasma are higher. The spatial profiles of the plasma density and electron temperature are also different in both axial and radial directions for these two kinds of helical antenna. The wavelength calculated based on the dispersion relation of the bounded whistler wave is consistent with the order of magnitude of plasma length. It is proved that the helicon plasma is part of the wave mode discharge mechanism.

关 键 词：helicon plasma non-uniform magnetic field helical antenna blue core discharge mechanism 

分 类 号：TN823.31[电子电信—信息与通信工程] O53[理学—等离子体物理]