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Title: The onset of plasma potential locking

Abstract

In this study, we provide insight into the role and impact that a positively biased electrode (anode) has on bulk plasma potential. Using two-dimensional Particle-in-Cell simulations, we investigate the plasma potential as an anode transitions from very small (“probe” mode) to large (“locking” mode). Prior theory provides some guidance on when and how this transition takes place. Initial experimental results are also compared. The simulations demonstrate that as the surface area of the anode is increased transitions in plasma potential and sheath polarity occur, consistent with experimental observations and theoretical predictions. It is expected that understanding this basic plasma behavior will be of interest to basic plasma physics communities, diagnostic developers, and plasma processing devices where control of bulk plasma potential is important.

Authors:
 [1];  [1];  [2];  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  2. Univ. of Iowa, Iowa City, IA (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1327907
Report Number(s):
SAND-2016-9434J
Journal ID: ISSN 1070-664X; PHPAEN; 647634
Grant/Contract Number:
AC04-94AL85000; AC04-94SL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 23; Journal Issue: 6; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; anodes; plasma sheaths; dielectrics; computational models; plasma diagnostics

Citation Formats

Hopkins, Matthew M., Yee, Benjamin T., Baalrud, Scott D., and Barnat, Edward V. The onset of plasma potential locking. United States: N. p., 2016. Web. doi:10.1063/1.4953896.
Hopkins, Matthew M., Yee, Benjamin T., Baalrud, Scott D., & Barnat, Edward V. The onset of plasma potential locking. United States. doi:10.1063/1.4953896.
Hopkins, Matthew M., Yee, Benjamin T., Baalrud, Scott D., and Barnat, Edward V. 2016. "The onset of plasma potential locking". United States. doi:10.1063/1.4953896. https://www.osti.gov/servlets/purl/1327907.
@article{osti_1327907,
title = {The onset of plasma potential locking},
author = {Hopkins, Matthew M. and Yee, Benjamin T. and Baalrud, Scott D. and Barnat, Edward V.},
abstractNote = {In this study, we provide insight into the role and impact that a positively biased electrode (anode) has on bulk plasma potential. Using two-dimensional Particle-in-Cell simulations, we investigate the plasma potential as an anode transitions from very small (“probe” mode) to large (“locking” mode). Prior theory provides some guidance on when and how this transition takes place. Initial experimental results are also compared. The simulations demonstrate that as the surface area of the anode is increased transitions in plasma potential and sheath polarity occur, consistent with experimental observations and theoretical predictions. It is expected that understanding this basic plasma behavior will be of interest to basic plasma physics communities, diagnostic developers, and plasma processing devices where control of bulk plasma potential is important.},
doi = {10.1063/1.4953896},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 4works
Citation information provided by
Web of Science

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  • In this paper, we provide insight into the role and impact that a positively biased electrode (anode) has on bulk plasma potential. Using two-dimensional Particle-in-Cell simulations, we investigate the plasma potential as an anode transitions from very small (“probe” mode) to large (“locking” mode). Prior theory provides some guidance on when and how this transition takes place. Initial experimental results are also compared. The simulations demonstrate that as the surface area of the anode is increased transitions in plasma potential and sheath polarity occur, consistent with experimental observations and theoretical predictions. It is expected that understanding this basic plasma behaviormore » will be of interest to basic plasma physics communities, diagnostic developers, and plasma processing devices where control of bulk plasma potential is important.« less
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