Atmospheric-Pressure Plasma Jet Produced by a Unipolar Nanosecond Pulse Generator in Various Gases

摘要

Atmospheric-pressure plasma jet provides an effective mode for many potential applications. Unipolar repetitive pulses of 25-ns rise time and 40-ns duration are used to drive a single electrode plasma jet in open air. He, Ar, $hbox{N}_{2}$, and air are chosen as the feed gases. Kinds of images of the observed plasma jets are presented under different experimental conditions. The diffusive appearances with $hbox{N}_{2}$ or air flow are different from the needle-like mode with He or Ar flow.