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Title: Different roles of electron beam in two stream instability in an elliptical waveguide for generation and amplification of THz electromagnetic waves

Abstract

In this work, two stream instability in a metallic waveguide with elliptical cross-section and with a hollow annular dielectric layer is studied for generation and amplification of THz electromagnetic waves. Dispersion relation of waves and their dependents to geometric dimensions and characteristics of the electron beam are analyzed. In continuation, the diagrams of growth rate for some operating frequencies are presented, so that effective factors on the growth rates, such as geometrical dimensions, dielectric constant of dielectric layer, accelerating voltage, and applied current intensity are analyzed. It is shown that while an electron beam is responsible for instability, another electron beam plays a stabilizing role.

Authors:
;  [1];  [2]
  1. Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan, Islamic Republic of Iran (Iran, Islamic Republic of)
  2. Department of Communications Engineering, Faculty of Electrical And Computer Engineering, University of Kashan, Kashan, Islamic Republic of Iran (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22599945
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 8; 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; AMPLIFICATION; CROSS SECTIONS; DIAGRAMS; DIELECTRIC MATERIALS; DISPERSION RELATIONS; DISPERSIONS; ELECTRIC POTENTIAL; ELECTROMAGNETIC RADIATION; ELECTRON BEAMS; ELECTRONS; LAYERS; PERMITTIVITY; TWO-STREAM INSTABILITY; WAVEGUIDES

Citation Formats

Safari, S., Jazi, B., E-mail: jaziada@kashanu.ac.ir, and Jahanbakht, S. Different roles of electron beam in two stream instability in an elliptical waveguide for generation and amplification of THz electromagnetic waves. United States: N. p., 2016. Web. doi:10.1063/1.4960383.
Safari, S., Jazi, B., E-mail: jaziada@kashanu.ac.ir, & Jahanbakht, S. Different roles of electron beam in two stream instability in an elliptical waveguide for generation and amplification of THz electromagnetic waves. United States. doi:10.1063/1.4960383.
Safari, S., Jazi, B., E-mail: jaziada@kashanu.ac.ir, and Jahanbakht, S. 2016. "Different roles of electron beam in two stream instability in an elliptical waveguide for generation and amplification of THz electromagnetic waves". United States. doi:10.1063/1.4960383.
@article{osti_22599945,
title = {Different roles of electron beam in two stream instability in an elliptical waveguide for generation and amplification of THz electromagnetic waves},
author = {Safari, S. and Jazi, B., E-mail: jaziada@kashanu.ac.ir and Jahanbakht, S.},
abstractNote = {In this work, two stream instability in a metallic waveguide with elliptical cross-section and with a hollow annular dielectric layer is studied for generation and amplification of THz electromagnetic waves. Dispersion relation of waves and their dependents to geometric dimensions and characteristics of the electron beam are analyzed. In continuation, the diagrams of growth rate for some operating frequencies are presented, so that effective factors on the growth rates, such as geometrical dimensions, dielectric constant of dielectric layer, accelerating voltage, and applied current intensity are analyzed. It is shown that while an electron beam is responsible for instability, another electron beam plays a stabilizing role.},
doi = {10.1063/1.4960383},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}
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