Self-mode-locked semiconductor lasers at 1.56 um

We report self-mode-locked semiconductor lasers at 1.56 um operating at 40 GHz repetition rate. These devices are based on enhanced Kerr lens mode-locking by vertically combining the active section with a passive waveguiding layer. The FWHM width of the pulse spectrum is over 8 nm and the time domain pulse duration is about 10 ps. The average output power coupled to a cleaved fiber is over 0 dBm.