An approximate k/spl middot/p theory for optical gain of strained InGaAsP quantum-well lasers

We describe an approximate k/spl middot/p theory for strained quantum wells that includes the bulk valence-band mixing effect and simplifies the envelope function approximation for the subband calculation. We show that such an approach provides analytical results for calculating the quasi-Fermi level and optical gain. We present useful material parameters over the whole parameter space of the InGaAsP system based on the approximate k/spl middot/p theory. Our approximate k/spl middot/p subband structure is compared with the results from the exact k/spl middot/p theory. Using a minimal set of fitting parameters, we show that the calculated gain spectrum agrees reasonably well with experimental data for the gain spectrum and its temperature dependence.<
>