ANALYSIS OF GAINP/ALGAINP COMPRESSIVE-STRAINED MULTIPLE-QUANTUM-WELL LASER

We have analyzed GaInP/AlGaInP compressive strained MQW lasers, with theoretical calculation and experimental results. Our calculations of TE polarized gain, where the valence subband mixing and the heterobarrier leakage current are taken into account, are in good agreement with the experimental results. When a compressive strain of up to 0.5% is induced in the quantum wells, the density of states near the valence band edge is decreased, due to the reduction of heavy-hole and light-hole subband mixing. At the threshold condition, the compressive strain reduces not only the radiative recombination current, but also the hetero-barrier leakage current. Therefore, the threshold current is reduced, and its temperature dependence is found to be small. In the analysis, we also show that when larger compressive strain of more than 0.5% is induced in the 40-angstrom-thick quantum wells, the threshold characteristics are degraded.