MODE-LOCKING AT VERY HIGH REPETITION RATES MORE THAN TERAHERTZ IN PASSIVELY MODE-LOCKED DISTRIBUTED-BRAGG-REFLECTOR LASER-DIODES

We propose a technique for achieving mode-locking at very high repetit ion rates more than terahertz with high output power using a distribut ed-Bragg-reflector (DBR) laser, including an intracavity saturable abs orber. This method is based on harmonic passive mode-locking at high g ain levels and the selectivity of harmonic numbers related to the spec trum-filtering property of the intracavity Bragg reflector. Transform- limited pulses at repetition rates from 500 GHz to 1.54 THz were gener ated with an output power exceeding 15 mW. We studied stability of har monic pulses by using conventional self-consistent mode-locking equati ons. We also discuss the effect of the spectrum-filtering properties o f the intracavity Bragg reflector to the characteristics of mode-locke d pulses.