Passively Mode-Locked High-Power (210 mW) Semiconductor Lasers at 1.55-$\mu$m Wavelength

We report on the generation of stable passively mode-locked pulses at 1.55-mum wavelength from high-power electrically pumped, large transverse mode semiconductor diode lasers. Optical pulses as short as 5.8 ps were measured directly from the laser. This is the shortest pulsewidth reported (without external compression) from a monolithic mode-locked slab coupled optical waveguide laser. The highest average power measured in mode-locked operation was 212 mW albeit the pulsewidths were larger. It was also found that length of the laser changes the power-current efficiency with the largest recorded efficiency of 165 mW/A.