480-GHz subharmonic synchronous mode locking in a short-cavity colliding-pulse mode-locked laser diode

Stabilization of a short cavity (174 μm) colliding-pulse mode-locked laser diode was successfully demonstrated by subharmonic synchronous mode locking with a subharmonic frequency optical pulse injection. A stable 480-GHz optical pulse train synchronized to an external clock signal with a low timing jitter of 0.14 ps was generated.