Subharmonic synchronous mode-locking of a monolithic semiconductor laser operating at millimeter-wave frequencies

Abstract

Optical pulse trains at millimeter-wave frequencies are generated by subharmonic synchronous mode-locking of a monolithic distributed Bragg reflector semiconductor laser, by which an initially passively mode-locked semiconductor laser is stabilized by injecting optical pulses at subharmonic frequencies of its resonant frequency. The stabilized pulse trains are characterized in terms of phase noise, timing jitter, locking range and modulation depth under various injection conditions including injected signal power levels, pulsewidths, and subharmonic numbers. It is also shown that subharmonic synchronous mode-locking can provide pulse trains with very low level of phase noise (≤ -86 dBc/Hz @ ..