Asymmetric Colliding-Pulse Mode-Locking in InGaAsP Semiconductor Lasers

Asymmetric colliding-pulse mode-locking was successfully demonstrated in an InGaAsP laser. This laser had a single saturable absorber section located partway along the cavity length, and showed mode-locking operation at harmonics of the cavity roundtrip frequency. The method verified that optical pulse repetition up to subterahertz rates can be generated with nearly 1-mm-long mode-locked InGaAsP lasers.