Dynamics in a compound cavity semiconductor laser induced by small external-cavity-length change

For the short-range variations of the external cavity length, the dynamic behaviors of a semiconductor laser with optical feedback are investigated by the numerical simulations and experiments. Under the condition of a single-mode oscillation, the laser output power shows periodic undulation along the external cavity length whose period is equal to half of the optical wavelength. At weak to moderate external optical feedback, stable, periodic, quasi-periodic, and chaotic oscillations of the laser output power are observed within the periodic undulation. Experimental results of periodic and quasi-periodic oscillations obtained by the laser output power and the optical spectrum support the predictions from the numerical analysis based on the rate equations.