Effect of well coupling on the TE optical modal gain in quantum-well-based semiconductor lasers

The role of coupling between two quantum wells in TE optical modal gain is analysed within the self-consistent solution of the Poisson, Schroedinger and 4x4 Luttinger-Kohn equations. The many-body effects of bandgap renormalization, coulombic scattering interactions and a non-Markovian distribution are also included. The analysis is performed for a 1.55 μm InGaAsP/InP lattice-matched system grown in the [001] direction. It shows that electrostatics significantly changes the modal gain in both amplitude and spectrum. The gain amplitude is larger when electrostatic effects are included due to better charge localization in the wells. The gain spectrum also changes due to the modification of the heterostructure potential and hence different coupling between the wells. (author). Letter-to-the-editor