Electric field during ns pulse discharge breakdown in ambient air has been measured by ps four-wave mixing, with temporal resolution of 0.2 ns. The measurements have been performed in a diffuse plasma generated in a dielectric barrier discharge, in plane-to-plane geometry. Absolute calibration of the electric field in the plasma is provided by the Laplacian field measured before breakdown. Sub-nanosecond time resolution is obtained by using a 150 ps duration laser pulse, as well as by monitoring the timing of individual laser shots relative to the voltage pulse, and post-processing four-wave mixing signal waveforms saved for each laser shot, placing them in the appropriate 'time bins'. The experimental data are compared with the analytic solution for time-resolved electric field in the plasma during pulse breakdown, showing good agreement on ns time scale. Qualitative interpretation of the data illustrates the effects of charge separation, charge accumulation/neutralization on the dielectric surfaces, electron attachment, and secondary breakdown. Comparison of the present data with more advanced kinetic modeling is expected to provide additional quantitative insight into air plasma kinetics on ∼ 0.1-100 ns scales.
Bibliographical noteFunding Information:
The support of US Department of Energy Plasma Science Center ‘Predictive Control of Plasma Kinetics: Multi-Phase and Bounded Systems’, and National Science Foundation grant ‘Nanosecond Pulse Discharges at a Liquid–Vapor Interface and in Liquids: Discharge Dynamics and Plasma Chemistry’, is gratefully acknowledged. We would also like to thank Dr David Burnette (Ohio University) for the extended loan of the Mega Impulse pulse generator, and Mr Edmond Baratte (Ecole Centrale Paris) for taking plasma emission images.
The support of US Department of Energy Plasma Science Center Predictive Control of Plasma Kinetics: Multi-Phase and Bounded Systems, and National Science Foundation grant Nanosecond Pulse Discharges at a Liquid-Vapor Interface and in Liquids: Discharge Dynamics and Plasma Chemistry, is gratefully acknowledged.
© 2017 IOP Publishing Ltd.
- electric field
- ns pulse breakdown
- ps four-wave mixing