Band-structure and optical gain for InAsP/In(GaAs)P MQW laser structures

Abstract

We present numerical results of the band structure of strain-compensated and strain-uncompensated InAsP/In(GaAs)P multi-quantum well (MQW) structures using the transfer-matrix algorithm based on the Luttinger–Kohn Hamiltonian. For the valence band, the heavy-hole band and the light-hole band are taken into account. The propagation matrices of the order 4×4 were obtained and used to get the solutions of the 4×4 Hamiltonian for the valence band. The valence-band-edge energies as well as the dispersion relations and valence-band mixing are calculated. The envelope wavefunctions of carriers for some QW structures and the optical gain for 1.3 μm InAsP/InGaAsP MQW lasers are calculated and discussed. We found that not only does the strain-compensation improve the quality of the MQW materials, also it modifies the band structure of MQW structures and hence modifies the modes of the optical output. Only TE mode output exists in our strain-compensated InAsP/InGaAsP MQW lasers.