Measurement of hexagonal super-lattice pattern in a dielectric barrier discharge

The hexagonal superlattice pattern is obtained in a dielectric barrier discharge at atmosphere pressure by using a discharge device with two water electrodes. It is found that the formation of the hexagon superlattice pattern depends on the mixture gas of air and argon. The bifurcation scenarios of the discharge pattern as the applied voltage increasing at different air-concentration are obtained. The results show that the hexagon superlattice pattern bifurcates from the dot-line pattern as the applied voltage increasing. A phase diagram of the pattern types as a function of gas component and applied voltage is presented. It reveals that the applied voltage for pattern formation increases with the air-concentration increasing.