Mode analysis of a dielectric-loaded raman-type free-electron laser

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · IEEE J. Quant. Electron.; (United States)

DOI:https://doi.org/10.1109/3.959· OSTI ID:7085115

Shibuya, Y; Shiozawa, T

The mode analysis of a dielectric-loaded Raman-type free-electron laser is developed. The Raman-type free-electron laser under consideration consists of a relativistic electron beam contained in a dielectric-loaded parallel plate waveguide and an array of permanent magnets for the wiggler. The beam and the dielectric are assumed to be arbitrary in thickness, with an arbitrary gap allowed between them. Under the influence of the periodic magnetostatic field, the coupling between the scattered electromagnetic wave of the TE mode (positive-energy wave) and the electron plasma wave of the TM mode (negative-energy wave) is investigated in detail. With the aid of numerical illustrations, the following interesting results are obtained. First, when a dielectric sheet is loaded on the waveguide, the maximum growth rate and the oscillation frequency can be greater than those for the vacuum Raman-type free-electron laser. Second, by choosing proper values for the relative permittivity of the dielectric sheet and the ratio of the beam thickness to the separation between the conducting walls of a waveguide, the authors can greatly ower the beam energy without degrading the oscillation characteristics. Third, the growth rate decays exponentially with the oscillation frequency kept almost constant as the beam-dielectric gap increases.

• Research Organization: Dept. of Electrical Communication Engineering, Osaka Univ., Suita, Osaka 565 (JP)
• OSTI ID: 7085115
• Journal Information: IEEE J. Quant. Electron.; (United States), Journal Name: IEEE J. Quant. Electron.; (United States) Vol. 24:7; ISSN IEJQA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
BEAMS
DIELECTRIC PROPERTIES
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELECTROMAGNETS
ELECTRON BEAMS
EQUIPMENT
FREE ELECTRON LASERS
FREQUENCY SELECTION
LASER SPECTROSCOPY
LASERS
LEPTON BEAMS
MAGNETS
NORMAL-MODE ANALYSIS
PARTICLE BEAMS
PHYSICAL PROPERTIES
PLASMA WAVES
RAMAN SPECTROSCOPY
SCATTERING
SPECTROSCOPY
WIGGLER MAGNETS