Radio frequency sheaths in an oblique magnetic field
Abstract
The physics of radiofrequency (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 onedimensional equations is developed that describes the dynamics of the timedependent magnetic presheath and nonneutral Debye sheath. The model employs MaxwellBoltzmann 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 electronpoor sheath, is otherwise arbitrary. Concentrating on the ioncyclotron 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 voltagecurrent relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheathplasma 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:
 Lodestar Research Corporation, 2400 Central Avenue, Boulder, Colorado 80301 (United States)
 Publication Date:
 OSTI Identifier:
 22489994
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 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; ONEDIMENSIONAL 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. doi:10.1063/1.4922848.
Myra, J. R., and D'Ippolito, D. A.. Mon .
"Radio frequency sheaths in an oblique magnetic field". United States.
doi: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 radiofrequency (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 onedimensional equations is developed that describes the dynamics of the timedependent magnetic presheath and nonneutral Debye sheath. The model employs MaxwellBoltzmann 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 electronpoor sheath, is otherwise arbitrary. Concentrating on the ioncyclotron 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 voltagecurrent relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheathplasma 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},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}

The physics of radiofrequency (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 onedimensional equations is developed that describe the dynamics of the timedependent magnetic presheath and nonneutral Debye sheath. The model employs MaxwellBoltzmann 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 electronpoor sheath, is otherwise arbitrary. Concentrating on the ioncyclotron range of frequencies, the equations are solved numericallymore »Cited by 6

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