Monolithic mode locking of long cavity GaAs-AlGaAs semiconductor lasers

A description is presented of active and hybrid mode locking of long 0.85- mu m monolithic semiconductor lasers. Active mode locking at 8.6 GHz is achieved by applying an RF modulation (with or without positive bias) to a short section of the cavity through a separate contact. By reverse biasing the contact and applying the RF modulation, hybrid mode locking is achieved, and in this case pulses of 16 ps duration are measured by a streak camera; although with some chirp, as indicated by a time-bandwidth product of 2.7. Partial passive mode locking is also achieved by application of a reverse bias to the split contact.<>