LOCKING CHARACTERISTICS OF A SUBHARMONICALLY HYBRID MODE-LOCKED MULTISECTION SEMICONDUCTOR-LASER

Locking characteristics of a subharmonically hybrid mode-locked (SH-ML ) semiconductor laser are investigated experimentally, The locking ban dwidths under the second- and third-order SH-ML operation, as well as under fundamental hybrid made-locking (FH-ML) condition, are character ized with a variety of microwave power and reverse bias voltage applie d to the saturable absorber of the laser, Unique locking characteristi cs are observed for the third-order SH-ML where the locking bandwidth increases with increasing reverse bias, which is opposite to the FH-ML case, This leads to a locking bandwidth of 56 MHz, 2.3 times broader than that for the FH-ML under the shortest pulse condition.