Novel self-hybrid mode-locking of semiconductor lasers in an external cavity

A new mode-locking method called self-hybrid mode-locking is explored. This method uses RF modulation at the sub-harmonic of pulse repetition frequency so that both active and passive mode-locking mechanisms operate in the same gain region without the necessity of additional integrated absorbers. With the same cavity configuration, self-hybrid mode-locking can generate pulses about 2/spl times/ shorter than the traditional active mode-locking.