Experimental studies of the difference between plasma potentials measured by Langmuir probes and emissive probes in presheaths
Experimental studies of the difference between plasma potentials measured by Langmuir probes and emissive probes in presheaths
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DOI：
10.1088/1361-6595/ab69e5
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发表时间：
2020-02-01
影响因子：
3.8
通讯作者：
Severn, Greg
中科院分区：
文献类型：
--
作者：
Li, Peixuan;Hershkowitz, Noah;Severn, Greg
圆柱形和平面朗缪尔探针测量的等离子体电位已被证明是不同的发射探针附近的预鞘附近的负偏置的电极浸入在弱碰撞低温氩等离子体中测量的等离子体电位。有两个主要的结果表明，在本文中。首先，虽然众所周知，朗缪尔探针不能可靠地测量鞘内的等离子体电位，这里提出的结果表明，问题仍然存在于presheaths，准中性等离子体边界鞘。已知在零发射极限下分析的发射探针精确地测量鞘层中的等离子体电势。现在很清楚，它们是唯一已知的静电探针技术，能够准确地测量整个预鞘的等离子体电位。第二，它表明，潜在的测量之间的差异由朗缪尔探针和发射探针在体内的等离子体，远比一个presheath距离的边界，是不成比例的T-e，如前所述。
The plasma potential measured by cylindrical and planar Langmuir probes has been shown to differ from the plasma potential measured by emissive probes in the neighborhood of the presheath near a negatively biased electrode immersed in a weakly collisional low temperature argon plasma. There are two principal results demonstrated in this paper. First, while it is well known that Langmuir probes cannot reliably measure plasma potentials inside of sheaths, results presented here demonstrate that the problem persists in presheaths, the quasineutral plasma bordering sheaths. It is known that emissive probes analyzed in the limit of zero emission accurately measure the plasma potential in the sheath. It is now clear that they are the only known electrostatic probe technique able to measure the plasma potential accurately throughout the presheath. Second, it is shown that the difference between potential measurements made by Langmuir probes and emissive probes in the body of the plasma, farther than a presheath distance from the boundary, is not proportional to T-e, as has been previously claimed.