Theoretical analysis of the gain of vertical cavity semiconductor optical amplifier

Considering the fact that power injection factor of the input signal is hard to evaluate when gain saturation is analyzed with existing rate equation models of vertical cavity semiconductor optical amplifier(VCSOA) according to the boundary condition of Fabry-Perot resonator,a gain model of VCSOA is established by using traveling-wave equation and position dependent carrier equation and employing gain enhancement factor which varies with axial position to describe the standing wave effect in a micro-cavity.After finding the self-consistent solution of equations based on the model,the distributions of carrier and photon in cavity are presented.Meanwhile,the reflection gain is investigated and agrees with the theoretical and experimental data.