摘要
Different discharge morphologies in atmospheric Ar and He plasmas are excited by using a pulsed microwave hairpin resonator. Ar plasmas form an arched plasma plume at the opened end of the hairpin, whereas He plumes generate only a contracted plasmas in between both tips of metal electrodes. Despite this different point, their discharge processes have three similar characteristics:(i) the ionization occurs at the main electrode firstly and then develops to the slave electrode,(ii) during the shrinking stage the middle domain of the discharge channels disappears at last, and(iii) even at zero power input(in between pulses) a weak light region always exists in the discharge channels. Both experimental results and electromagnetic simulations suggest that the discharge is resonantly excited by the local enhanced electric fields. In addition, Ar ionization and excitation energies are lower than those of He, the effect of Ar gas flow is far greater than that of He gas, and the contribution of accelerated electrons only locates at the domain with the strongest electric fields. These reasons could be used to interpret the different characteristic plume morphologies of the proposed atmospheric Ar and He plasmas.
Different discharge morphologies in atmospheric Ar and He plasmas are excited by using a pulsed microwave hairpin resonator. Ar plasmas form an arched plasma plume at the opened end of the hairpin, whereas He plumes generate only a contracted plasmas in between both tips of metal electrodes. Despite this different point, their discharge processes have three similar characteristics:(i) the ionization occurs at the main electrode firstly and then develops to the slave electrode,(ii) during the shrinking stage the middle domain of the discharge channels disappears at last, and(iii) even at zero power input(in between pulses) a weak light region always exists in the discharge channels. Both experimental results and electromagnetic simulations suggest that the discharge is resonantly excited by the local enhanced electric fields. In addition, Ar ionization and excitation energies are lower than those of He, the effect of Ar gas flow is far greater than that of He gas, and the contribution of accelerated electrons only locates at the domain with the strongest electric fields. These reasons could be used to interpret the different characteristic plume morphologies of the proposed atmospheric Ar and He plasmas.
作者
陈兆权
周本宽
张煌
洪伶俐
邹长林
李平
赵卫东
刘晓东
Olga Stepanova
A A Kudryavtsev
Zhao-Quan Chen1, Ben-Kuan Zhou, Huang Zhang1, Ling-Li Hong1, Chang-Lin Zou1, Ping Li1, Wei-Dong Zhao1, Xiao-Dong Liu1, Olga Stepanova2, and A A Kudryavtsev2(1 School of Electrical & Information Engineering, Anhui University of Technology, Maanshan 243032, China; 2Faculty of Physics, St. Petersburg State University, St. Petersburg 198504, Russi)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.11575003 and 51607003)