Mainz 2022 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

P: Fachverband Plasmaphysik

P 7: Atmospheric Pressure Plasmas I

P 7.2: Talk

Tuesday, March 29, 2022, 14:15–14:30, P-H11

Breakdown and quasi-DC phase of a nanosecond discharge — •Nikita Lepikhin¹, Jan Kuhfeld¹, Zoltán Donkó^1,2, Dirk Luggenhölscher¹, and Uwe Czarnetzki¹ — ¹Institute for Plasma and Atomic Physics, Ruhr University Bochum, D-44780 Bochum, Germany — ²Wigner Research Centre for Physics, Budapest, Hungary

A nanosecond Atmospheric Pressure Plasma Jet (ns-APPJ) is studied by picosecond Electric-Field Induced Second Harmonic generation (E-FISH) and spatially/temporally resolved Optical Emission Spectroscopy (OES). Two distinct phases of the discharge are identified: fast breakdown at high electric field is followed by a quasi-DC phase at lower permanent electric field and high electron density. The spatial structure of the discharge after the breakdown is found to be similar to that of a DC-glow discharge. It is demonstrated that the bulk electric field in the quasi-DC phase is independent of the amplitude of the voltage applied to the discharge and, consequently, the electric field strength during breakdown. It is also shown that the voltage and current waveforms and the discharge morphology weakly depend on the gas mixture. The experimental results are compared with the results of PIC/MCC simulations and an analytical model. Good agreement is found throughout.