An Ultrahigh Current Density Micro Discharge

At atmospheric pressure, a micro thin-cathode discharge operates in a self-pulsing mode with a peak current density of several 10⁵ A/cm². The V-I characteristic of the discharge indicates that the self-pulsing is due to a periodic ignition of a spark discharge. In the self-pulsing mode, the plasma emission was observed by a CCD camera. The camera image proved that the discharge produces strongly localized sparks in the self-pulsing mode.