Behaviour of fully ionized seed plasma excited by microwave
Behaviour of fully ionized seed plasma excited by microwave
复制标题
微波激发的完全电离种子等离子体的行为
DOI：
10.1109/27.557480
复制
发表时间：
1997
期刊：
影响因子：
--
通讯作者：
S. Kabashima
中科院分区：
文献类型：
--
作者：
T. Murakami;T. Suekane;Y. Okuno;S. Kabashima
用微波功率在中等气压的氦气和氩气中激发金属铯蒸气电离的非平衡等离子体。种子等离子体的结构和行为的实验研究，特别是在全种子（铯原子）电离的条件下。通过铯籽晶，维持等离子体的最小功率显著降低，并且在纯氦中观察到的宽等离子体和在纯氩中观察到的不稳定的类顺磁等离子体都转变为靠近放电管内表面的稳定的宽等离子体。电子温度测量表明，在适当的微波功率下，等离子体可以处于完全籽晶电离区，其中电子密度几乎保持恒定。完全电离种子等离子体（FIS）的厚度随着铯蒸气摩尔分数的增加而减小，并且几乎与惰性气体压力无关。厚度几乎与从FIS等离子体中几乎均匀的电导率确定的趋肤深度一致。这些事实表明，只要微波功率用于电子加热，FIS等离子体就很容易产生和维持。
Nonequilibrium plasmas with cesium metal vapor ionization in helium and argon gases at moderate pressures are excited with microwave power. The structures and behaviour of the seeded plasmas are experimentally examined, particularly under the condition of Full seed (cesium atoms) ionization. By cesium seeding, the minimum power sustaining the plasma is reduced markedly, and both a broad plasma observed in pure helium and unsteady filament-like plasmas in pure argon change to the steady and broad plasma locating close to the inner surface of a discharge tube, it is revealed from the electron temperature measurements that the plasma can be in the regime of full seed ionization for suitable microwave powers, where the electron density is kept almost constant. The thickness of the fully ionized seed (FIS) plasma decreases with increasing the mole fraction of cesium vapor, and is almost independent of noble gas pressure. The thickness almost coincides with the skin depth determined from the electrical conductivity almost uniform in the FIS plasma. These facts suggest that the FIS plasma will be easily produced and maintained as long as the microwave power is consumed to the electron heating.