Semiconductor lasers are important in high-speed optical communications for many reasons. Perhaps the greatest advantage that semiconductor lasers have over other technologies is that their optical output can be modulated directly by varying the injection current. Until now, however, modulation bandwidths have been rather inconveniently limited. A single-mode semiconductor laser cannot be effectively modulated beyond its relaxation oscillation frequency, typically 10 GHz.
© 1991 Optical Society of AmericaPDF Article