Title :
Single-mode operation and linewidth reduction of a GRECC multimode semiconductor laser
Author :
Chan, Y.F. ; Cormack, G.D.
Author_Institution :
Alberta Telecommun. Res. Center, Edmonton, Alta., Canada
Abstract :
A technique is presented for easily converging a multimode semiconductor laser to a single-mode operation by utilizing a far-end coated GRIN-ROD lens to provide simultaneously side-mode suppression, linewidth reduction, a collimated beam from one side of the configuration, and a usable beam from the other facet of the laser. Side-mode suppression (SMS) of at least 22 dB was achieved. The linewidth of the laser was reduced from 90 MHz to 8.5 MHz with a10%-reflectivity lens and to 4 MHz with a 40%-reflectivity lens at 1.7 Ith. A SMS of at least 17 dB was preserved under two separate conditions of high-frequency (450 MHz) and large-signal modulation
Keywords :
gradient index optics; lenses; optical modulation; semiconductor junction lasers; 22 dB; 450 MHz; 8.5 MHz; GRECC multimode semiconductor laser; GRIN ROD external coupled cavity; collimated beam; far-end coated GRIN-ROD lens; large-signal modulation; linewidth reduction; sidemode suppression; singlemode operation; Fabry-Perot interferometers; Fiber lasers; Frequency; Laser beams; Laser feedback; Laser modes; Laser noise; Lenses; Reflectivity; Semiconductor lasers;
Conference_Titel :
WESCANEX 88: 'Digital Communications Conference Proceedings'
Conference_Location :
Saskatoon, Sask.
DOI :
10.1109/WESCAN.1988.27680
