Ionization wave propagation on a micro cavity plasma array
  Microcavity plasma arrays of inverse pyramidal cavities have been fabricated in p-Si wafers. Each cavity acts as a microscopic dielectric barrier discharge. Operated at atmospheric pressure in argon and excited with high voltage at about 10 kHz, each cavity develops a localized microplasma. Experiments have shown a strong interaction of individual cavities, leading to the propagation of wave-like optical emission structures along the surface of the array. This phenomenon is numerically investigated using computer simulation. The observed ionization wave propagates with a speed of about 5 km/s, which agrees well the experimental findings. It is found that the wave propagation is due to sequential contributions of a drift of electrons followed by drift of ions between cavities seeded by photoemission of electrons by the plasma in adjacent cavities. 
Alexander Wollny, Torben Hemke, Markus Gebhardt, Ralf Peter Brinkmann,   Henrik Boettner, Joerg Winter, Volker Schulz-von de...
physics.plasm-ph