Title :
Enhancement of frequency-tunability for a Smith-Purcell free-electron laser in the millimeter-wave region
Author :
Shiozawa, T. ; Muya, T. ; Hirata, A. ; Kawasaki, Z.
Author_Institution :
Chubu Univ., Aichi, Japan
Abstract :
The frequency-tunability for a Smith-Purcell free-electron laser in the millimeter wave region is enhanced with the aid of a quasi-periodic distributed Bragg reflector (DBR) made of metallic waveguide gratings with rectangular grooves. For a quasi-periodic DBR, the grating parameters are adjusted by means of genetic algorithms to get the desired reflection coefficient, thus compensating for the frequency dependence of the overall output characteristics. For a typical numerical example, flat output characteristics have been obtained over 10 % bandwidth around the center frequency 121 GHz.
Keywords :
Bragg gratings; free electron lasers; genetic algorithms; waveguides; 121 GHz; Smith-Purcell free-electron laser; frequency-tunability; genetic algorithms; grating parameters; metallic waveguide gratings; millimeter-wave region; quasiperiodic distributed Bragg reflector; rectangular grooves; reflection coefficient; Bandwidth; Bragg gratings; Distributed Bragg reflectors; Free electron lasers; Frequency dependence; Genetic algorithms; Laser modes; Optical reflection; Rectangular waveguides; Waveguide lasers;
Conference_Titel :
Microwave Conference, 2005 European
Print_ISBN :
2-9600551-2-8
DOI :
10.1109/EUMC.2005.1610127
