A quasi-three-dimensional large-signal dynamic model of distributed feedback lasers

A simple, but powerful, quasi-three-dimensional large-signal dynamic model of distributed feedback semiconductor laser is presented. The transient response of lasers is analyzed by using a combined beam propagation method and time-domain algorithm that is capable of including the longitudinal and lateral variation of the optical-mode and carrier density profiles. In addition, the spontaneous emission noise, the nonuniform current injection resulting from the variation of Fermi-voltage as well as that of the refractive index distribution are also taken into consideration. Using this model, the influence of nonuniform waveguide structure on the static and dynamic responses of distributed feedback lasers is analyzed. In addition, a novel double tapered waveguide distributed feedback laser is proposed for stable single-mode operation at high power.