The uniform propagation of positive-polarity surface plasmas in air at atmospheric pressure has been achieved using a multi-layer structure, consisting of a silicon wafer covered by a 1 μ m thick dielectric SiO 2 layer as a propagation surface. Instead of the branched streamers observed in the same conditions when using conventional bulk dielectric surfaces, the plasma exhibits a homogenous ring-shaped structure with a high degree of reproducibility and stability. The plasma is generated by applying nanosecond positive voltage pulses to a tungsten wire touching the dielectric surface. The plasma has been imaged in single shot operation at high spatial resolution with an ultraviolet reflective microscope coupled with a fast intensified charge-coupled device camera. Time- and space-resolved optical emission spectroscopy shows that the homogenous ring corresponds to the propagation of an ionization front with a region of high N 2 +* emission. We...

中文翻译：

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阴极指向的表面电离波在大气压下的均匀传播

使用多层结构已经实现了大气压下正极表面等离子体在空气中的均匀传播，该多层结构由被1μm厚介电SiO 2层覆盖的硅晶片作为传播表面组成。代替使用传统的体电介质表面在相同条件下观察到的支流，等离子体显示出具有高再现性和稳定性的均质环形结构。通过向与电介质表面接触的钨丝施加纳秒级的正电压脉冲来生成等离子体。等离子体已通过紫外反射显微镜和快速增强的电荷耦合器件照相机在单次操作中以高空间分辨率成像。时间和空间分辨的光发射光谱表明，均匀环对应于具有高N 2 + *发射区域的电离前沿的传播。我们...