Cutoff frequency of toroidal plasma waveguide
Abstract
The cutoff frequencies of E and Hmodes of empty and plasma filled toroidal waveguides are evaluated. The effects of space curvature and plasma density on cutoff frequencies for both modes are investigated. Using a suitable variable change, a scalar wave equation in the direction of propagation was obtained. The study indicates that the curvature in the direction of wave propagation in toroidal waveguide has an analogous effect as a straight waveguide filled with anisotropic media. The RayleighSchrodinger perturbation method was employed to solve for cutoff frequencies in the first order of approximation. In the limit of small space curvature, the toroidal waveguide cutoff frequencies for both E and Hmodes approach those of TM and TE modes of empty cylindrical waveguide with a radius equal to toroidal waveguide minor radius. The analysis shows that the curvature in the direction of propagation in toroidal waveguides leads to the removal of the degeneracy between E and Hmodes.
 Authors:
 Department of Physics, University of Tehran, Tehran 14399 (Iran, Islamic Republic of)
 Publication Date:
 OSTI Identifier:
 22408074
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 2; 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; ANISOTROPY; CYLINDRICAL CONFIGURATION; DISTURBANCES; HMODE PLASMA CONFINEMENT; PLASMA DENSITY; TOROIDAL CONFIGURATION; WAVE EQUATIONS; WAVEGUIDES
Citation Formats
ZakeriKhatir, H., and Aghamir, F. M.. Cutoff frequency of toroidal plasma waveguide. United States: N. p., 2015.
Web. doi:10.1063/1.4907795.
ZakeriKhatir, H., & Aghamir, F. M.. Cutoff frequency of toroidal plasma waveguide. United States. doi:10.1063/1.4907795.
ZakeriKhatir, H., and Aghamir, F. M.. 2015.
"Cutoff frequency of toroidal plasma waveguide". United States.
doi:10.1063/1.4907795.
@article{osti_22408074,
title = {Cutoff frequency of toroidal plasma waveguide},
author = {ZakeriKhatir, H. and Aghamir, F. M.},
abstractNote = {The cutoff frequencies of E and Hmodes of empty and plasma filled toroidal waveguides are evaluated. The effects of space curvature and plasma density on cutoff frequencies for both modes are investigated. Using a suitable variable change, a scalar wave equation in the direction of propagation was obtained. The study indicates that the curvature in the direction of wave propagation in toroidal waveguide has an analogous effect as a straight waveguide filled with anisotropic media. The RayleighSchrodinger perturbation method was employed to solve for cutoff frequencies in the first order of approximation. In the limit of small space curvature, the toroidal waveguide cutoff frequencies for both E and Hmodes approach those of TM and TE modes of empty cylindrical waveguide with a radius equal to toroidal waveguide minor radius. The analysis shows that the curvature in the direction of propagation in toroidal waveguides leads to the removal of the degeneracy between E and Hmodes.},
doi = {10.1063/1.4907795},
journal = {Physics of Plasmas},
number = 2,
volume = 22,
place = {United States},
year = 2015,
month = 2
}

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