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Title: Three-dimensional particle-in-cell simulations of 300 GHz reflex klystrons

Abstract

Three-dimensional (3D) particle-in-cell simulations of 300 GHz reflex klystrons are presented. 300 GHz electromagnetic wave generation in a resonant cavity is analyzed by using a 3D simulation model in which all the geometric parameters (such as the grid thickness, repeller shape, beam radius, etc.) are described. When an electron beam of an energy of 1.0 keV and a net current of 8.9 mA is used, the maximum electronic efficiency of energy transfer is observed when the gap transit angle is 0.7{pi} rad, and the efficiency saturates when the beam current is over 10 mA. Space charge forces produce a shift in the optimum repeller voltage. It is also shown that the effect of the beam temperature is not critical, even though the bunching wavelength of the electron beam is several times smaller than that in conventional vacuum electron devices. Our simulation results show that a microfabricated 300 GHz reflex klystron can directly generate electromagnetic waves with output power levels of several tens of milliwatts.

Authors:
; ; ; ;  [1]
  1. Korea Electrotechnology Research Institute (KERI), 28-1, Sung-Ju Dong, Changwon, Gyungnam 641-120 (Korea, Republic of)
Publication Date:
OSTI Identifier:
20982736
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 5; Other Information: DOI: 10.1063/1.2710353; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 43 PARTICLE ACCELERATORS; BEAM CURRENTS; CAVITY RESONATORS; COMPUTERIZED SIMULATION; ELECTRIC POTENTIAL; ELECTROMAGNETIC RADIATION; ELECTRON BEAMS; ENERGY TRANSFER; GHZ RANGE 100-1000; KLYSTRONS; MATHEMATICAL MODELS; SPACE CHARGE; THREE-DIMENSIONAL CALCULATIONS; WAVELENGTHS

Citation Formats

Jeon, S. G., Jin, Y. S., Kim, J. I., Kim, G. J., and Shon, C. H.. Three-dimensional particle-in-cell simulations of 300 GHz reflex klystrons. United States: N. p., 2007. Web. doi:10.1063/1.2710353.
Jeon, S. G., Jin, Y. S., Kim, J. I., Kim, G. J., & Shon, C. H.. Three-dimensional particle-in-cell simulations of 300 GHz reflex klystrons. United States. doi:10.1063/1.2710353.
Jeon, S. G., Jin, Y. S., Kim, J. I., Kim, G. J., and Shon, C. H.. Thu . "Three-dimensional particle-in-cell simulations of 300 GHz reflex klystrons". United States. doi:10.1063/1.2710353.
@article{osti_20982736,
title = {Three-dimensional particle-in-cell simulations of 300 GHz reflex klystrons},
author = {Jeon, S. G. and Jin, Y. S. and Kim, J. I. and Kim, G. J. and Shon, C. H.},
abstractNote = {Three-dimensional (3D) particle-in-cell simulations of 300 GHz reflex klystrons are presented. 300 GHz electromagnetic wave generation in a resonant cavity is analyzed by using a 3D simulation model in which all the geometric parameters (such as the grid thickness, repeller shape, beam radius, etc.) are described. When an electron beam of an energy of 1.0 keV and a net current of 8.9 mA is used, the maximum electronic efficiency of energy transfer is observed when the gap transit angle is 0.7{pi} rad, and the efficiency saturates when the beam current is over 10 mA. Space charge forces produce a shift in the optimum repeller voltage. It is also shown that the effect of the beam temperature is not critical, even though the bunching wavelength of the electron beam is several times smaller than that in conventional vacuum electron devices. Our simulation results show that a microfabricated 300 GHz reflex klystron can directly generate electromagnetic waves with output power levels of several tens of milliwatts.},
doi = {10.1063/1.2710353},
journal = {Journal of Applied Physics},
number = 5,
volume = 101,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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