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DOE OSTI · 1980304

Higher Harmonics in Multipactor Induced Plasma Ionization Breakdown near a Dielectric Surface

Wen, De-Qi·Zhang, Peng·Krek, Janez·Fu, Yangyang·Verboncoeur, John P.
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Abstract

In this Letter, the novel physics of higher harmonic (HH) generation of the normal electric field near a dielectric surface is reported in multipactor induced plasma ionization breakdown, as determined by kinetic particle-in-cell simulations. The observed HH frequency is around ten times the fundamental rf driving frequency, but lower than the electron plasma frequency. A theory is constructed which indicates that stream plasma interaction-induced instability is the mechanism of HH generation in the collisional regime. The HH frequency and its corresponding growth rate of the HH oscillation amplitude from the theory are in good agreement with kinetic particle-in-cell simulations.

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60 APPLIED LIFE SCIENCESPhysicshigh-frequency & RF discharges in plasmaslow-temperature plasmaparticle-in-cell methodsplasma discharges in vacuumplasma ionizationplasma microinstabilitiesplasma sheaths & surfacestwo-fluid & multi-fluid model

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Wen, De-Qi, Zhang, Peng, Krek, Janez, Fu, Yangyang, Verboncoeur, John P.. 2022-07-20. Higher Harmonics in Multipactor Induced Plasma Ionization Breakdown near a Dielectric Surface. https://doi.org/10.1103/physrevlett.129.045001

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