Pulsation stabilization and enhancement in self-pulsating laser diodes

The authors report stabilization and enhancement of the optical pulses of self-pulsating laser diodes using a combination of self-injection locking and frequency locked loops. A record short term stability of one part in 1,500,000 (3 dB linewidth of less than 800 Hz at 1.3 GHz) was readily achieved with continuous tunability from 600 MHz to over 3 GHz (harmonics to over 12 GHz). The reduction in timing jitter resulted in a <10 dB improvement of the signal-to-noise ratio, making self-pulsating lasers a potential source of ultrastable picosecond pulses in both the optical and the electrical domains. The latter characteristics make self-pulsating lasers an attractive candidate for widely tunable microwave oscillators or sources for optical (electrical) sampling.<
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