Ps four-wave mixing measurements of electric field in nanosecond pulse discharges in ambient air

Marien Simeni Simeni, Edmond Baratte, Cheng Zhang, Kraig Frederickson, Igor V. Adamovich

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Electric field in nanosecond pulse discharges in ambient air is measured by picosecond four-wave mixing. Absolute calibration of the electric field is provided by the Laplacian field measured before breakdown, or by a separate measurement of a known electrostatic field. The measurements are done for two cases, (a) discharge between two parallel plate electrodes placed inside quartz sleeves, and (b) discharge between a razor edge electrode and distilled water surface. In the first case, breakdown field exceeds DC breakdown threshold by approximately a factor of two, 75 ± 7.5 kV/cm. The electric field follows the applied voltage before breakdown and decreases rapidly after breakdown, due to charge separation and plasma self-shielding. Sub-nanosecond time resolution (up to 0.2 ns) is obtained 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”. In the second case, electric field is measured for both positive and negative pulse polarities, with pulse durations of ~ 10 ns and ~ 100 ns, respectively. In the short duration, positive polarity pulse, breakdown occurs at 85 kV/cm, after which the electric field decreases over several ns due to charge separation in the plasma, with no field reversal detected when the applied voltage is reduced. In the long duration, negative polarity pulse, breakdown occurs at a lower electric field, 30 kV/cm, after which the field decays over several tens of ns and reverses direction when the applied voltage is reduced at the end of the pulse. For both pulse polarities, electric field after the pulse decays on a microsecond time scale, due to residual surface charge neutralization by transport of opposite polarity charges from the plasma. Measurements 1 mm away from the discharge center plane, ~ 100 μm from the water surface, show that during the voltage rise, horizontal field component (Ex) lags in time behind the vertical component (Ey). After breakdown, Ey is reduced to near zero and reverses direction. Further away from the water surface (≈ 0.9 mm), Ex is much higher compared to Ey during the entire voltage pulse. The results provide insight into air plasma kinetics and charge transport processes near plasma-liquid interface, over a wide range of time scales.

Original languageEnglish (US)
Title of host publicationAIAA Aerospace Sciences Meeting
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
Edition210059
ISBN (Print)9781624105241
DOIs
StatePublished - Jan 1 2018
Externally publishedYes
EventAIAA Aerospace Sciences Meeting, 2018 - Kissimmee, United States
Duration: Jan 8 2018Jan 12 2018

Publication series

NameAIAA Aerospace Sciences Meeting, 2018
Number210059

Other

OtherAIAA Aerospace Sciences Meeting, 2018
CountryUnited States
CityKissimmee
Period1/8/181/12/18

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Cite this

Simeni Simeni, M., Baratte, E., Zhang, C., Frederickson, K., & Adamovich, I. V. (2018). Ps four-wave mixing measurements of electric field in nanosecond pulse discharges in ambient air. In AIAA Aerospace Sciences Meeting (210059 ed.). (AIAA Aerospace Sciences Meeting, 2018; No. 210059). American Institute of Aeronautics and Astronautics Inc, AIAA. https://doi.org/10.2514/6.2018-1429