Visualization of Revolving Modes in RF and MW Nonthermal Atmospheric Pressure Plasma Jets

The high-speed sequence imaging of two different atmospheric pressure plasma jets illuminates the low-frequency dynamics of discharge filaments. Usually, atmospheric plasma jets consist of several contracted filaments occurring in the active zone of the plasma randomly in space and stochastically in time. However, particular plasma excitation schemes support collective regimes where the filaments are self-organized at large spatial and temporal scales, even at atmospheric pressure. Moreover, self-organized dynamics can act in a similar manner at different types of plasma. In this paper, evident similarities in filament patterning are pointed out for radio-frequency and microwave atmospheric pressure jets by publishing images of short exposure time (6 ms) from which the filament movement can be derived.