One-dimensional simulation of a free-electron laser oscillator using a diffraction grating as a cavity mirror

Conference · Fri Jan 01 04:00:00 EST 1988

DOI:https://doi.org/10.1016/0168-9002(89)90450-6· OSTI ID:7011935

Takeda, H; Sollid, J E

The free-electron laser (FEL) oscillator is known to excite parasitic sideband wavelengths in addition to the fundamental wavelengths at high intracavity power. When a tapered wiggler is used, the sidebands reduce the extraction efficiency. To eliminate the sidebands and to increase the extraction efficiency, we studied an FEL cavity with one of the mirrors ruled as a diffraction grating. The diffraction grating deflects the light in the cavity selectively according to the wavelength: the sidebands can be eliminated by deflection to off-axis of the cavity. Because the grating mirror must be mounted with an angle, laser pulse is stretched after diffraction. The pulse stretching reduces optical intensity. We studied the effect of pulse stretching numerically using a one-dimensional FEL code FELP. Using this code, the free-electron laser performance is calculated and compared with different line densities of grating for the following three wigglers: an untapered wiggler, a 12% wavelength tapered wiggler, and a wiggler tapered in wave number by 30%. The wavelength aperture caused by the grating also is studied as a function of line density. 2 refs., 11 figs.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7011935
• Report Number(s): LA-UR-88-3613; CONF-8808146-4; ON: DE89002292
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
BEAM EXTRACTION
CAVITIES
COMPUTERIZED SIMULATION
EFFICIENCY
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
EQUIPMENT
FREE ELECTRON LASERS
GRATINGS
LASER MIRRORS
LASERS
MAGNETS
MIRRORS
SIMULATION
WAVELENGTHS
WIGGLER MAGNETS