Threshold Reduction for a Diode Laser by using the Technique of Optical Feedback

Abstract

In this experimental work, the dynamics of a distributed feedback semiconductor laser was studied. Dynamics in free running for a solitary laser was satisfied experimentally, and then dynamics in the present of optical feedback, via a free space as a waveguide, was studied experimentally. Results showed that the insertion of strong level of optical feedback led the laser emission to be instable due to a bifurcation. The higher feedback level make the laser operating in the so called coherence collapse, which means that the dominant operating mode, and any modulated modes within this range could be translated securely inside a controlled chaos.