Locking characteristics of semiconductor lasers with optical injection

Abstract

We have studied the locking characteristics of semiconductor lasers through numerical calculation of the output intensity and change in carrier density of the slave laser during injection locking. We have also obtained the dynamic locking range by examining the roots of the secular determinant of the perturbed system. The lower boundaries of the static and dynamic locking ranges coincide, but the upper boundaries do not. Both the static and dynamic locking ranges are asymmetrical about zero detuning and dependent on injection ratio, linewidth enhancement factor and biasing condition. The upper boundary of the dynamically stable region exhibits an abrupt bend at a very low injection level. Unlike previous work, the locking characteristics at both low and high injection levels have been carefully studied.