We have solved the rate equations for InGaAs/GaAs self-assembled quantum-dot laser considering homogeneous and inhomogeneous broadening of optical gain numerically using fourth-order Runge-Kutta method. Dynamic-characteristics are analyzed; relaxation oscillation frequency, modulation bandwidth, and turn-on delay improve as injection current increases. With enhancing of the full width at half maximum (FWHM) of homogeneous broadening, threshold current and turn-on delay increase, because of elevating of central group density of states. Simulation results of static-characteristics show that slope-efficiency increases as the FWHM of homogeneous broadening heightens due to enhancing of central group carriers. Exceeding of the FWHM of homogeneous broadening from FWHM of inhomogeneous broadening results in degradation of slope-efficiency and static-characteristics because empty DOS increas. Nonlinearity appears in light-current characteristics at a special interval from ratio of FWHM of homogeneous broadening to FWHM of inhomogeneous broadening. Differential gain decreases as initial relaxation time and recombination times heighten. Consequently, relaxation oscillation frequency and modulation bandwidth decline.

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