Numerical modeling of the output and operations of semiconductor lasers subject to strong optical feedback and its dependence on the linewidth-enhancement factor

Abstract

Influence of the linewidth-enhancement factor on the output and operations of InGaAs/InP pumping lasers emitting at a wavelength of 980 nm under strong optical feedback is investigated numerically. The investigations are performed based on intensive numerical integration of an improved time-delay rate equations of semiconductor lasers over wide ranges of the linewidth-enhancement factor and optical feedback strength. The results show that the semiconductor laser operates under strong optical feedback in continuous wave and pulsation at small values of the linewidth-enhancement factor. Under large values of the linewidth-enhancement factor, the laser happens to exhibit chaos and pulsation. We predict that semiconductor laser subjected to strong optical feedback exhibits much more stable pulsing operation under higher values of the linewidth-enhancement factor, which indicates that the laser is locked at the external cavity frequency. © 2010 John Wiley & Sons, Ltd.