Controlling chaos of a laser diode with all external optical delaytime feedback

A method of controlling chaos of a laser diode with all external optical feedback was proposed according to the principle of Pyragas method. Firstly, we added a team of optical feedback into the equations of laser diode with external optical delay-time feedback and analyzed the conditions in which the method can be used were given from theoretical analysis based on the coherence theory. Secondly, the maximum Lyapunov exponent (MLE) of the controlled system was computed and the ranges in which MLE was smaller than zero and the chaos was controlled were found. Finally, the attractor and the power spectra of the system were given. The efficiency of the method was proved by the computer simulation.