Millimeter-wave signal generation from a monolithic semiconductor laser via subharmonic optical injection

A new technique for generating millimeter-wave (mm-wave) signals from a semiconductor laser without an intracavity saturable absorber, is presented, The method multiplies the signal frequency by using optical injection of short optical pulses at a subharmonic of the cavity round-trip frequency to drive the laser oscillating at its resonant frequency. A 34.64 GHz signal is generated using a multisection semiconductor laser operated under continuous wave conditions, by injecting optical pulses at a repetition rate equal to the fourth subharmonic (8.66 GHz). The generated millimeter-wave signal exhibits a large subharmonic suppression ratio (>17 dB), large frequency detuning range (>300 MHz), low levels of phase-noise (-77.5 dBc/Hz), and large locking range (>400 MHz).