Laser spectroscopic determination of electric fields, electron densities, and electron temperatures in atmospheric pressure microdischarges

激光电场测量和汤姆逊散射可以提供对微放电中主要等离子体参数的非侵入性诊断。特别是可以测量等离子体密度、电子速度分布函数和局域电场，其时间分辨率和空间分辨率均优于100μm。激光测量与超快和光谱分辨光学诊断和电学测量相结合。适用于纳秒脉冲和射频操作的喷气式飞机。虽然后一种喷气式飞机已经在研究小组中投入使用，但ns-喷气式飞机是一个新的发展。与只需要在氦中使用小分子混合物的射频喷注不同，纳秒喷注中的短高压脉冲将允许在分子气体中直接操作。特别是，在氮气中运行将允许直接测量电场。诊断学提供的数据将作为这些微等离子体的模拟和模型的基准。

Laser electric field measurements and Thomson scattering can provide non-intrusive diagnostics of major plasma parameters in microdischarges. In particular plasma densities, the electron velocity distribution function, and the local electric field can be measured with ns-time resolution and spatial resolutions of better than 100 μm. The laser measurements are combined with ultra-fast and spectrally resolved optical diagnostics and electrical measurements. Application will be to ns-pulsed and RF-operated jets. While the latter jets are already operational in the research group, the ns-jets are a novel development. In contrast to the RF-jets which require operation in helium with only small molecular admixtures, the short high voltage pulses in the ns-jets will allow direct operation in molecular gases. In particular, operation in nitrogen will allow direct electric field measurements. The data provided by the diagnostics will serves as benchmarks for simulations and models of these micro plasmas.