The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Bahram Jazi - One of the best experts on this subject based on the ideXlab platform.
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AZIMUTHAL Electromagnetic Surface Waves IN A ROD DIELECTRIC MAGNETIZED PLASMA WAVEGUIDE AND THEIR EXCITATION BY AN ANNULAR RELATIVISTIC ROTATING ELECTRON BEAM
Plasma Physics and Controlled Fusion, 2006Co-Authors: Bahram Jazi, Babak Shokri, H. ArbabAbstract:The dispersion relation of azimuthal Electromagnetic Surface Waves in a rod dielectric magnetized plasma waveguide is obtained. It is investigated that these Waves in E-type can be excited by a thin annular relativistic rotating electron beam (TARREB). The effects of the rotating velocity of beam, radius TARREB, on the frequency spectra and growth-rate coefficient are presented.
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Excitation of Electromagnetic Surface Waves by an annular electron beam in a plasma waveguide with a dielectric rod and a magnetized plasma column
Plasma Physics and Controlled Fusion, 2004Co-Authors: Bahram Jazi, Babak ShokriAbstract:The dispersion relation for symmetrical TM Electromagnetic Surface Waves propagating in a plasma waveguide with a strongly magnetized plasma column and a dielectric rod is investigated. The growth rate for excitation of these Waves is obtained and its dependence on the radius of the annular beam, current intensity and accelerating voltage are investigated.
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Dispersion relation of azimuthal Electromagnetic Surface Waves on a magnetized plasma column in a dielectric lined slow-wave waveguide
Plasma Physics and Controlled Fusion, 2004Co-Authors: Bahram Jazi, Hassan MehdianAbstract:The dispersion relation of azimuthal Electromagnetic Surface Waves on a magnetized plasma column surrounded by a metallic cylindrical dielectric lined slow-wave waveguide is obtained. The permissible frequency region for these Waves in E- and B-mode is presented. Furthermore, the graphs of frequency spectra and radial dependence of fields on the external magnetic field strength, geometric dimensions of the waveguide, radius of plasma column and thickness of dielectric are investigated.
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Azimuthal Electromagnetic Surface Waves on an annular magnetized plasma
Physics Letters A, 2003Co-Authors: Babak Shokri, Bahram JaziAbstract:The dispersion relation of azimuthal Electromagnetic Surface Waves propagating perpendicular to the external magnetic field on an annular magnetized plasma rotating around the symmetric axis in a cylindrical metallic waveguide is obtained. The frequency region for E-modes and B-modes is investigated. Furthermore, the graphs of frequency spectra and radial dependency of the electric fields on the external magnetic field strength, geometric dimensions of the waveguide, and thickness of the annular plasma are presented.
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Excitation of nonreciprocal Electromagnetic Surface Waves in semibounded magnetized plasmas by an electron beam
Physics of Plasmas, 2003Co-Authors: Babak Shokri, Bahram JaziAbstract:The dispersion relation of nonreciprocal Electromagnetic Surface Waves propagating on the magnetized plasma–vacuum interface is obtained. Furthermore, the dependency of penetration depth on the magnetic field strength and its directivity is investigated. Finally, it will be shown that by an electron beam flowing on the plasma Surface, aforementioned Waves can be excited.
Jorge Gaspararmenta - One of the best experts on this subject based on the ideXlab platform.
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Electromagnetic Surface Waves at a metal 2d photonic crystal interface
Journal of The Optical Society of America B-optical Physics, 2013Co-Authors: Jorge Gaspararmenta, F VillavillaAbstract:The conditions to observe and excite Electromagnetic Surface modes at the interface between a two-dimensional (2D) photonic crystal (PC) and bulk metal are studied. It is shown that these modes can exist in the region where bandgaps of the PC overlap with the region below the plasma frequency of a metal in the dispersion diagram in both polarizations. The dispersion relation of these Electromagnetic Surface modes is determined numerically by considering a system of a thin metallic layer in contact with a finite PC of some periods. The reflectance is computed by using the finite-difference time-domain (FDTD) method. With this method, it is shown that these modes can be excited and observed even under normal incidence from a vacuum. For the studied system, the cell in contact with the metallic layer must be truncated in order to observe the interface mode. It is shown that we can select the frequency of the mode inside the bandgaps by properly choosing the truncation parameter.
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Electromagnetic Surface Waves photonic crystal photonic crystal interface
Optics Communications, 2003Co-Authors: Francisco Villa, Jorge GaspararmentaAbstract:It is demonstrated the existence of Electromagnetic Surface modes at the interface of two different one-dimensional photonic crystals. Contrary to common behavior of modes present at the Surfaces of truncated photonic crystals embedded in dielectric media, these modes can reside above and below the light line for vacuum within the overlapping of band gaps of both photonic crystals. This behavior implies that they can be excited and observed without prism or grating configurations even under normal incidence from vacuum if proper conditions are fulfilled.
Babak Shokri - One of the best experts on this subject based on the ideXlab platform.
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AZIMUTHAL Electromagnetic Surface Waves IN A ROD DIELECTRIC MAGNETIZED PLASMA WAVEGUIDE AND THEIR EXCITATION BY AN ANNULAR RELATIVISTIC ROTATING ELECTRON BEAM
Plasma Physics and Controlled Fusion, 2006Co-Authors: Bahram Jazi, Babak Shokri, H. ArbabAbstract:The dispersion relation of azimuthal Electromagnetic Surface Waves in a rod dielectric magnetized plasma waveguide is obtained. It is investigated that these Waves in E-type can be excited by a thin annular relativistic rotating electron beam (TARREB). The effects of the rotating velocity of beam, radius TARREB, on the frequency spectra and growth-rate coefficient are presented.
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Excitation of Electromagnetic Surface Waves by an annular electron beam in a plasma waveguide with a dielectric rod and a magnetized plasma column
Plasma Physics and Controlled Fusion, 2004Co-Authors: Bahram Jazi, Babak ShokriAbstract:The dispersion relation for symmetrical TM Electromagnetic Surface Waves propagating in a plasma waveguide with a strongly magnetized plasma column and a dielectric rod is investigated. The growth rate for excitation of these Waves is obtained and its dependence on the radius of the annular beam, current intensity and accelerating voltage are investigated.
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Azimuthal Electromagnetic Surface Waves on an annular magnetized plasma
Physics Letters A, 2003Co-Authors: Babak Shokri, Bahram JaziAbstract:The dispersion relation of azimuthal Electromagnetic Surface Waves propagating perpendicular to the external magnetic field on an annular magnetized plasma rotating around the symmetric axis in a cylindrical metallic waveguide is obtained. The frequency region for E-modes and B-modes is investigated. Furthermore, the graphs of frequency spectra and radial dependency of the electric fields on the external magnetic field strength, geometric dimensions of the waveguide, and thickness of the annular plasma are presented.
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Excitation of nonreciprocal Electromagnetic Surface Waves in semibounded magnetized plasmas by an electron beam
Physics of Plasmas, 2003Co-Authors: Babak Shokri, Bahram JaziAbstract:The dispersion relation of nonreciprocal Electromagnetic Surface Waves propagating on the magnetized plasma–vacuum interface is obtained. Furthermore, the dependency of penetration depth on the magnetic field strength and its directivity is investigated. Finally, it will be shown that by an electron beam flowing on the plasma Surface, aforementioned Waves can be excited.
F Villavilla - One of the best experts on this subject based on the ideXlab platform.
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Electromagnetic Surface Waves at a metal 2d photonic crystal interface
Journal of The Optical Society of America B-optical Physics, 2013Co-Authors: Jorge Gaspararmenta, F VillavillaAbstract:The conditions to observe and excite Electromagnetic Surface modes at the interface between a two-dimensional (2D) photonic crystal (PC) and bulk metal are studied. It is shown that these modes can exist in the region where bandgaps of the PC overlap with the region below the plasma frequency of a metal in the dispersion diagram in both polarizations. The dispersion relation of these Electromagnetic Surface modes is determined numerically by considering a system of a thin metallic layer in contact with a finite PC of some periods. The reflectance is computed by using the finite-difference time-domain (FDTD) method. With this method, it is shown that these modes can be excited and observed even under normal incidence from a vacuum. For the studied system, the cell in contact with the metallic layer must be truncated in order to observe the interface mode. It is shown that we can select the frequency of the mode inside the bandgaps by properly choosing the truncation parameter.
M Moisan - One of the best experts on this subject based on the ideXlab platform.
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Electromagnetic Surface Waves for a new approach to the investigation of plasmas produced at electron cyclotron resonance (ECR)
Journal of Physics D: Applied Physics, 1991Co-Authors: J Margot, M MoisanAbstract:The authors propose and put to use a new approach to studying magnetised plasmas sustained by a high frequency (HF) field, particularly aiming at examining the case of discharges achieved at electron cyclotron resonance. This approach considers the methodology and the formalism of the modeling of cylindrical plasma columns produced by Electromagnetic Surface Waves and extends them to the case where these discharges are submitted to an axial, static magnetic field B0. It leads to a variety of Waves that are guided by the plasma column, these Waves differing in particular by the spatial distribution of their electric field intensity. This distribution plays on the power transfer from the HF field to the plasma and it influences the spatial density distribution of excited atoms. This led them to analyse, as a function of B0, the respective effects of the wave attenuation coefficient, wave polarization and HF power required to maintain an electron-ion pair in the discharge upon the plasma density and upon the electric field for the gas breakdown.
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plasma sources based on the propagation of Electromagnetic Surface Waves
Journal of Physics D, 1991Co-Authors: M Moisan, Z ZakrzewskiAbstract:Microwave and RF plasmas are finding increasing use in materials processing, plasma chemistry, chemical analysis, and other fields. This is stimulating the search for suitable plasma sources. In the 1970s, Electromagnetic Surface Waves were put to use to sustain plasmas and an efficient microwave device, called a surfatron, was developed for this purpose. Recent work has shown that such discharges can also operate at radio frequencies. A large number of on Surface-wave plasmas experimental data have been accumulated-their modelling is well advanced and they have found applications in various fields of research and technology. This paper reviews the physical principles of operation and the design of Surface-wave plasma sources. Since the wave launcher is the central component of the source, this review presents a unified description of several compact, efficient, and easy to operate launchers specifically intended for plasma generation that have been developed over the past fifteen years. It is now possible to sustain such plasmas at frequencies ranging from 1 MHz to 10 GHz, in a pressure domain extending from 10-5 Torr up to few times atmospheric pressure, and in a rich variety of plasma vessels and reaction chambers.