Abstract

The generation of high-repetition-rate optical pulses from semiconductor lasers is of great importance for ultrahigh-speed optical time-division-multiptexed com munications. Passively mode-locked lasers have the potential to provide pulse trains well beyond the modulation bandwidth of semiconductor lasers. Recently it has been shown that the large phase noise associated with such devices can be suppressed to sufficiently low levels by using the hybrid mode-locking technique, where a modulation signal corresponding to the laser cavity round trip time is applied to the saturable absorber.¹ However, such a technique meets difficulties as the frequency extends to higher mm-wave frequencies due to the device parasitics and high costs of stable microwave sources. In this paper we report, we believe, the first demonstration of hybrid mode-locking of a 33-GHz multisection semiconductor laser by subharmonic modulation.

© 1996 Optical Society of America