A METHOD TO DETERMINE THE ABOVE-THRESHOLD STABILITY OF DISTRIBUTED-FEEDBACK SEMICONDUCTOR-LASER DIODES

An analysis of the above-threshold stability of distributed feedback ( DFB) semiconductor laser diodes (LD's) is presented. It is based on a numerical model which takes into account effects of spatial hole burni ng (SHE) and the nonlinear gain coefficient, In the analysis, the Newt on-Raphson (NR) technique has not been used, and no functional derivat ive is required, Taking into account the presence of another nonlasing mode, the single-mode stability of the DFB laser diodes is determined , The proposed model does not depend on any particular DFB structure, and hence can be applied to various DFB LD structures, Numerical resul ts are presented for a three-phase-shift (3PS) DFB LD.