Electronic states in a separate confinement heterostructure: a comparative study

The electronic states in separate confinement heterostructure quantum well GaAs-GaAl_0.18As_0.82 lasers are studied within the effective-mass approximation by using the generalized impedance method. The emphasis is placed on the dependence of the main interband transition energies and of the overlap integrals on the key parameters such as the well width and the shape of the confinement structure. The main interband transition energies for the rectangular structures are in agreement with previous results. Compared with a rectangular well or a parabolic well, the triangular well structure presents a greater confinement of the electron and the hole. As a result, the overlap between their associated wave functions is smaller, leading to a reduction of the interband recombination