A 250 Hz spectral linewidth 1.5 mu m MQW-DFB laser diode with negative-electrical-feedback

A 1.5 mu m corrugation-pitch-modulated MQW-DFB laser diode (LD) with multielectrodes was frequency stabilized using the negative electrical feedback technique. The FM response of the LD was precisely measured and used for the feedback loop design. The FM noise of the LD was reduced and reached 10 Hz/sup 2//Hz at 1 kHz>