Abstract

With the drive to higher data rates for short (<50 km) local distribution trunks, the push for 10 Gbit/s source has increased. Integrated distributed feedback (DFB)/electroabsorption modulation devices provide an attractive source at 1.55 μm¹ as their low chirp allows transmission through standard fiber (zero dispersion at 1.3 μm) over tens of kilometers. These links become attractive if the design does not require an erbium-doped fiber amplifier, which increases system cost and complexity. This limitation puts a premium on high source output power, and therefore favors simple DFB lasers, which provide higher coupled output power than more complex integrated devices. The main limitation of 1.55-μm DFB lasers is wavelength chirp, with the system requiring very low values of the linewidth enhancement factor ‘.’ Sources operating at 1.3 μm have no such dispersion related problems, however they require far higher output powers to overcome the higher fiber loss at that wavelength.

© 1996 Optical Society of America