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Title: Radio frequency sheaths in an oblique magnetic field

Abstract

The physics of radio-frequency (rf) sheaths near a conducting surface is studied for plasmas immersed in a magnetic field that makes an oblique angle θ with the surface. A set of one-dimensional equations is developed that describes the dynamics of the time-dependent magnetic presheath and non-neutral Debye sheath. The model employs Maxwell-Boltzmann electrons, and the magnetization and mobility of the ions is determined by the magnetic field strength, and wave frequency, respectively. The angle θ, assumed to be large enough to insure an electron-poor sheath, is otherwise arbitrary. Concentrating on the ion-cyclotron range of frequencies, the equations are solved numerically to obtain the rectified (dc) voltage, the rf voltage across the sheath, and the rf current flowing through the sheath. As an application of this model, the sheath voltage-current relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheath-plasma interface that can be used in rf wave codes. In general, the impedance has both resistive and capacitive contributions, and generalizes previous sheath boundary condition models. The resistive part contributes to parasitic power dissipation at the wall.

Authors:
;  [1]
  1. Lodestar Research Corporation, 2400 Central Avenue, Boulder, Colorado 80301 (United States)
Publication Date:
OSTI Identifier:
22489994
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BOLTZMANN STATISTICS; BOUNDARY CONDITIONS; CURRENTS; ELECTRIC FIELDS; ELECTRIC POTENTIAL; ELECTRONS; ION MOBILITY; MAGNETIC FIELDS; MAGNETIZATION; ONE-DIMENSIONAL CALCULATIONS; PLASMA; PLASMA SHEATH; RADIOWAVE RADIATION; SURFACES; TIME DEPENDENCE; WALLS

Citation Formats

Myra, J. R., and D'Ippolito, D. A. Radio frequency sheaths in an oblique magnetic field. United States: N. p., 2015. Web. doi:10.1063/1.4922848.
Myra, J. R., & D'Ippolito, D. A. Radio frequency sheaths in an oblique magnetic field. United States. https://doi.org/10.1063/1.4922848
Myra, J. R., and D'Ippolito, D. A. Mon . "Radio frequency sheaths in an oblique magnetic field". United States. https://doi.org/10.1063/1.4922848.
@article{osti_22489994,
title = {Radio frequency sheaths in an oblique magnetic field},
author = {Myra, J. R. and D'Ippolito, D. A.},
abstractNote = {The physics of radio-frequency (rf) sheaths near a conducting surface is studied for plasmas immersed in a magnetic field that makes an oblique angle θ with the surface. A set of one-dimensional equations is developed that describes the dynamics of the time-dependent magnetic presheath and non-neutral Debye sheath. The model employs Maxwell-Boltzmann electrons, and the magnetization and mobility of the ions is determined by the magnetic field strength, and wave frequency, respectively. The angle θ, assumed to be large enough to insure an electron-poor sheath, is otherwise arbitrary. Concentrating on the ion-cyclotron range of frequencies, the equations are solved numerically to obtain the rectified (dc) voltage, the rf voltage across the sheath, and the rf current flowing through the sheath. As an application of this model, the sheath voltage-current relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheath-plasma interface that can be used in rf wave codes. In general, the impedance has both resistive and capacitive contributions, and generalizes previous sheath boundary condition models. The resistive part contributes to parasitic power dissipation at the wall.},
doi = {10.1063/1.4922848},
url = {https://www.osti.gov/biblio/22489994}, journal = {Physics of Plasmas},
issn = {1070-664X},
number = 6,
volume = 22,
place = {United States},
year = {2015},
month = {6}
}

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    Works referencing / citing this record:

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    dataset, April 2017


    Physics-Based Parametrization Of The Surface Impedance For Radio Frequency Sheaths [Supplemental Data]
    dataset, April 2017


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    journal, January 2019


    Numerical model of the radio-frequency magnetic presheath including wall impurities
    journal, September 2019


    Numerical solutions of Maxwell's equations in 3D in frequency domain with linear sheath boundary conditions
    journal, August 2019


    Calculation of RF sheath properties from surface wave-fields: a post-processing method
    journal, July 2019