A LOW-VOLTAGE WAVE-GUIDE FREE-ELECTRON LASER-BASED ON A LONGITUDINAL INTERACTION MECHANISM

Authors
Citation
Mg. Kong, A LOW-VOLTAGE WAVE-GUIDE FREE-ELECTRON LASER-BASED ON A LONGITUDINAL INTERACTION MECHANISM, Optics communications, 141(1-2), 1997, pp. 48-52
Citations number
19
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Optics
Journal title
ISSN journal
0030-4018
Volume
141
Issue
1-2
Year of publication
1997
Pages
48 - 52
Database
ISI
SICI code
0030-4018(1997)141:1-2<48:ALWFLO>2.0.ZU;2-T
Abstract
Low current waveguide free electron lasers (FELs) operating in the spe ctrum from microwave to the infrared have a distinct advantage of smal l size and low cost? important for realistic applications in medicine and industry, One of the long-term objectives in the development of th ese compact FELs is to reduce the necessary electron beam voltage for a strong FEL interaction at a given frequency. In this paper, we consi der a longitudinal interaction between the longitudinal component of t he electron beam's undulating motion and the longitudinal electric fie ld of TM modes of the waveguide electromagnetic wave. A small signal a nalysis is presented to study the longitudinal interaction mechanism. It is shown that the electron beam voltage can be reduced considerably from what is needed in the conventional transverse interaction of the electron beam with TE modes at the same frequency. In a design exampl e of an X-band FEL amplifier, this reduction is found to be more than half. Gain calculation suggests that with a reasonable wiggler field s uch a. longitudinal interaction leads to a sizeable FEL amplification of TM modes. (C) 1997 Elsevier Science B.V.