Abstract

Directly modulated semiconductor lasers are of great interest for low cost transmitter applications in short reach optical data transmission systems. Recently it was shown theoretically [1] and experimentally [2], that a two section passive feedback laser (PFL) consisting of an active DFB and a passive integrated feedback (IFB) sections can demonstrate a suitable perfonnance under direct current modulation at 40 Gb/s rate (see Fig. 1). In contrast to solitary DFB lasers, the interaction of longitudinal compound cavity modes of this PFL can imply an enhancement of the modulation bandwidth. The required neighbouring mode in the PFL is excited by a sufficiently high properly delayed and phase tuned optical feedback into the active DFB section. The feedback control is realized by the IFB section [1].

© 2007 IEEE