Coherent photon seeding of actively mode locked laser diodes

We have applied a coherent photon seeding technique to actively mode locked laser diodes for the first time and successfully achieved a single longitudinal laser diode mode operation with a side mode suppression ratio of −20 dB. We have also proposed a new kind of pulse compressor consisting of a grating and a plane mirror, which gives positive group velocity dispersion. We obtained 11 ps pulses with spectral width of 0.32 nm. This gives us a time bandwidth product of 0.63, which is approximately twice the transform limited value for a sech2 pulse.