Evolution from the gradient drift instability to the formation of the spoke potential hump in a partially magnetized plasma
Rotating spokes commonly occur in partially magnetized plasma devices. This work explores the evolution from the gradient drift instability into an m = 1 rotating spoke mode in a magnetically enhanced hollow cathode discharge (with emissive cathode) by means of 2D radial-azimuthal particle-in-cell/M...
Gespeichert in:
Veröffentlicht in: | Physics of plasmas 2023-07, Vol.30 (7) |
---|---|
Hauptverfasser: | , , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Rotating spokes commonly occur in partially magnetized plasma devices. This work explores the evolution from the gradient drift instability into an m = 1 rotating spoke mode in a magnetically enhanced hollow cathode discharge (with emissive cathode) by means of 2D radial-azimuthal particle-in-cell/Monte Carlo collision simulations. It is shown that the formation of the spoke potential hump region can be explained as a result of the local collapse of the anode sheath due to the gradient drift instability, which is triggered within the anode sheath. The sheath non-neutrality effect on the instability is considered and incorporated in the two-fluid linear theory of gradient drift instability. The unstable modes predicted by the theory are in good agreement with the fluctuation modes developed in the particle simulations. |
---|---|
ISSN: | 1070-664X 1089-7674 |
DOI: | 10.1063/5.0156778 |