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Title: The charge imbalance in ultracold plasmas

Abstract

Ultracold plasmas are regarded as quasineutral but not strictly neutral. The results of charge imbalance in the expansion of ultracold plasmas are reported. The calculations are performed by a full molecular-dynamics simulation. The details of the electron velocity distributions are calculated without the assumption of electron global thermal equilibrium and Boltzmann distribution. Spontaneous evolutions of the charge imbalance from the initial states with perfect neutrality are given in the simulations. The expansion of outer plasma slows down with the charge imbalance. The influences of plasma size and parameters on the charge imbalance are discussed. The radial profiles of electron temperature are given for the first time, and the self-similar expansion can still occur even if there is no global thermal equilibrium. The electron disorder induced heating is also found in the simulation.

Authors:
; ; ;  [1]
  1. Key Laboratory for Quantum Optics and Center for Cold Atom Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)
Publication Date:
OSTI Identifier:
22599861
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOLTZMANN STATISTICS; COMPUTERIZED SIMULATION; DISTRIBUTION; ELECTRON TEMPERATURE; ELECTRONS; HEATING; MOLECULAR DYNAMICS METHOD; PLASMA; THERMAL EQUILIBRIUM; VELOCITY

Citation Formats

Chen, Tianxing, Lu, Ronghua, E-mail: lurh@siom.ac.cn, Guo, Li, and Han, Shensheng. The charge imbalance in ultracold plasmas. United States: N. p., 2016. Web. doi:10.1063/1.4961957.
Chen, Tianxing, Lu, Ronghua, E-mail: lurh@siom.ac.cn, Guo, Li, & Han, Shensheng. The charge imbalance in ultracold plasmas. United States. doi:10.1063/1.4961957.
Chen, Tianxing, Lu, Ronghua, E-mail: lurh@siom.ac.cn, Guo, Li, and Han, Shensheng. Thu . "The charge imbalance in ultracold plasmas". United States. doi:10.1063/1.4961957.
@article{osti_22599861,
title = {The charge imbalance in ultracold plasmas},
author = {Chen, Tianxing and Lu, Ronghua, E-mail: lurh@siom.ac.cn and Guo, Li and Han, Shensheng},
abstractNote = {Ultracold plasmas are regarded as quasineutral but not strictly neutral. The results of charge imbalance in the expansion of ultracold plasmas are reported. The calculations are performed by a full molecular-dynamics simulation. The details of the electron velocity distributions are calculated without the assumption of electron global thermal equilibrium and Boltzmann distribution. Spontaneous evolutions of the charge imbalance from the initial states with perfect neutrality are given in the simulations. The expansion of outer plasma slows down with the charge imbalance. The influences of plasma size and parameters on the charge imbalance are discussed. The radial profiles of electron temperature are given for the first time, and the self-similar expansion can still occur even if there is no global thermal equilibrium. The electron disorder induced heating is also found in the simulation.},
doi = {10.1063/1.4961957},
journal = {Physics of Plasmas},
number = 9,
volume = 23,
place = {United States},
year = {Thu Sep 15 00:00:00 EDT 2016},
month = {Thu Sep 15 00:00:00 EDT 2016}
}
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