Honeycomb hexagon pattern in dielectric barrier discharge

Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Oct;76(4 Pt 2):046210. doi: 10.1103/PhysRevE.76.046210. Epub 2007 Oct 10.

Abstract

We report on a honeycomb hexagon pattern in dielectric barrier discharge. It bifurcates from a square pattern as the applied voltage is increased. A phase diagram of the pattern types as a function of the gas component and applied voltage is presented. The spatial Fourier spectrum of the honeycomb hexagon pattern is a hexagonal superstructure with three wave vectors k[over ]_{1};{h} , k[over ]_{2};{s} and k[over ]_{3};{s} at least, demonstrating that the pattern is a superlattice pattern. Measurements of the correlation between discharge filaments indicate that the honeycomb hexagon pattern is an interleaving of three different transient hexagonal sublattices, whose spatial wave vectors are exactly equal to k[over ]_{1};{h} , k[over ]_{2};{s} and k[over ]_{3};{s} , respectively. These three wave modes fulfill a triad resonance condition k[over ]_{3};{s}-k[over ]_{2};{s}=k[over ]_{1};{h} .