Physics and Simulation of Helicon Plasma Sources

Scharer9905948这项研究的目标包括对氦等离子体源(n_e=10^11-10^13/cm^3)的新的实验测量和计算模拟，这对未来的各种应用是重要的。其中包括晶片的亚微米等离子体刻蚀，材料的加工，用于氩激光的高效电离源，用于模拟空间等离子体实验的大体积源，用于聚变等离子体约束实验的源，核废料处理器，以及用作航天器的防锈剂。到目前为止，这些源尚未解决的关键问题是：1)产生快速电离电子的机制(在Ar E 16 eV中)及其在空间和时间上的能量分布函数的测量，这是在太阳源中有效电离的关键；2)在非均匀磁场配置中快速空间衰减波的机制和改进源操作的新天线的实现；3)波天线耦合、线性加热和非线性波捕获过程的二维模拟，这些过程可以与实验观测相比较，并用于预测未来太阳源的特性，这对该领域是新的。我们开发了一种新的实验装置，它将利用快速响应光学探头、指示快电子的高能Ar态光谱、波场、频谱分析、朗缪尔探头和抗磁回路以及网络分析技术来测量匹配的天线阻抗。我们将开发一个二维等离子体轮廓、有限差分、全电磁程序(MAXEB)，并将其与实验观测进行比较。对等离子体产生的物理和这些源的模拟技术的更好的理解将为极大地改进天线和磁场源的设计和用于各种应用的更大尺寸的等离子体源提供基础。我们的新实验计划与模拟计划的紧密结合为我们在这一新兴技术领域的未来应用提供了一个特殊的机会。*

Scharer9905948The objectives of this research include new experimentalmeasurements and computational simulations of heliconplasma sources (n_e=10^11 - 10^13/cm^3) which areimportant for a variety of future applications. Theseinclude submicron plasma etching of wafers, processingof materials, an efficient ionization source for argonlasers, a large volume source for simulation of space-plasmaexperiments, a source for fusion plasma confinementexperiments, a processor of nuclear waste, and as athrustor for space vehicles. Key issues which have notbeen resolved to date for these sources are: 1) Mechanismsfor producing fast ionizing electrons (in argon E 16 eV)and measurements of their energy distribution function inspace and time, which are key to efficient ionization in heliconsources, 2) Mechanisms for rapid spatial damping of the wavein inhomogeneous magnetic field configurations and realizationof new antennas which improve source operation, 3) 2-Dsimulations of wave antenna coupling, linear heating, andnonlinear wave trapping processes, which can be comparedwith experimental observations and utilized to predict futurehelicon source properties which is new to the field. We havedeveloped a new experimental facility which will utilize asdiagnostics a fast response optical probe, spectroscopyof energetic argon states indicative of fast electrons, wavefield, frequency spectral analysis, Langmuir probe anddiamagnetic loops and network analyzer techniques tomeasure the matched antenna impedance. We will develop a 2-D plasma profile, finite-difference, full electromagnetic code (MAXEB) which will be compared with experimental observations. The improved understanding of the physics of plasma production and simulation techniques for these sources will provide a basis for greatly improved antenna and magnetic field source design and larger size plasma sources for a variety of applications. The close coupling of our new experimental program with simulation programs provides an exceptional opportunity for improving our knowledge for future applications in this emerging technology area.***