Self organization in dielectric barrier discharge and control of hexagonal structures

Symmetric self organized discharge filaments have been observed in the 140$\mu$m microgap dielectric barrier discharge between two parallel glass plates. The spatial distribution of these discharge filaments were revealed by a discharge experiment in which the thickness of dielectric barrier and pressure were changed. An image of the discharge in nano seconds was obtained using an intensified charge-coupled device (ICCD) camera. The diameters of the self-organized filaments, and the distance between them were obtained using the ICCD images. We found that if the dielectric barrier is thinner then the lattice spacing (the distance between the filaments) are smaller. In addition, the lattice spacing at 760 Torr was smaller than that at 380 torr. Numerical calculation showed the same tendency for lattice spacing as the hexagonal pattern structures in the discharge experiments. Therefore, the lattice spacing of hexagonal patterns can be controlled by manipulating the control parameters in an experiment.