Band Structure and Optical Gain of InGaAs/GaAsBi Type-II Quantum Wells Modeled by the k\cdot p Model

Optical gains of type-II InGaAs/GaAsBi quantum wells (QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k\cdot p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-II QWs are a promising structure for making 1.3 μm lasers at room temperature because they can easily be used to obtain 1.3 μm for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain.