Differential gain in InP-based strained layer multiple quantum well lasers

Compressive biaxial strain has been predicted to enhance the small-signal modulation bandwidth of quantum well lasers, owing to increased differential gain in these devices. However, the effect of tensile strain on these devices is less clear. We have investigated the effects of both compressive and tensile strain on the differential gain for multiple quantum well lasers with In,Ga,-As quantum wells for 0.33<~<0.73. We observe markedly increased differential gain for both compressive and tensile strain, indicating that large modulation bandwidths can be obtained in both cases.