Threedimensional theory of the Cerenkov freeelectron laser
Abstract
We describe an analytical theory for the gain of a Cerenkov freeelectron laser including diffraction of the optical beam in the direction transverse to the electron beam, parallel to the surface of the dielectric. Since the width of the optical beam depends on the gain, the usual cubic dispersion relation of twodimensional slowwave structures is replaced by a 5/2power dispersion relation, but three of the five roots are extraneous. The results show that for a narrow electron beam, the optical beam is much wider than the electron beam. This reduces the gain by an order of magnitude. Moreover, in the threedimensional theory the allowed roots of the dispersion relation have positive real parts, so they correspond to slow waves; when transverse diffraction is included, fast waves are forbidden.
 Authors:
 Department of Physics, Vanderbilt University, Nashville, Tennessee 37235 (United States)
 Publication Date:
 OSTI Identifier:
 20982902
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 10; Other Information: DOI: 10.1063/1.2734540; (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; DIELECTRIC MATERIALS; DIFFRACTION; DISPERSION RELATIONS; ELECTRON BEAMS; FREE ELECTRON LASERS; THREEDIMENSIONAL CALCULATIONS; TWODIMENSIONAL CALCULATIONS
Citation Formats
Andrews, H. L., and Brau, C. A.. Threedimensional theory of the Cerenkov freeelectron laser. United States: N. p., 2007.
Web. doi:10.1063/1.2734540.
Andrews, H. L., & Brau, C. A.. Threedimensional theory of the Cerenkov freeelectron laser. United States. doi:10.1063/1.2734540.
Andrews, H. L., and Brau, C. A.. Tue .
"Threedimensional theory of the Cerenkov freeelectron laser". United States.
doi:10.1063/1.2734540.
@article{osti_20982902,
title = {Threedimensional theory of the Cerenkov freeelectron laser},
author = {Andrews, H. L. and Brau, C. A.},
abstractNote = {We describe an analytical theory for the gain of a Cerenkov freeelectron laser including diffraction of the optical beam in the direction transverse to the electron beam, parallel to the surface of the dielectric. Since the width of the optical beam depends on the gain, the usual cubic dispersion relation of twodimensional slowwave structures is replaced by a 5/2power dispersion relation, but three of the five roots are extraneous. The results show that for a narrow electron beam, the optical beam is much wider than the electron beam. This reduces the gain by an order of magnitude. Moreover, in the threedimensional theory the allowed roots of the dispersion relation have positive real parts, so they correspond to slow waves; when transverse diffraction is included, fast waves are forbidden.},
doi = {10.1063/1.2734540},
journal = {Journal of Applied Physics},
number = 10,
volume = 101,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

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