EFFECTS OF STRAIN AND COULOMB INTERACTION ON GAIN AND REFRACTIVE-INDEX IN QUANTUM-WELL LASERS

The eigenstates of the coupled-band Luttinger Hamiltonian are used to derive modified optical Bloch equations for strained layer semiconduct or heterostructures. An average effective-mass approximation is introd uced, and the single-plasmon-pole approximation for the screened Coulo mb interaction is extended for the multiple-subband case. Spectra of t he optical absorption/gain and of the antiguiding (linewidth enhanceme nt) factor are computed by use of a high-density Pade approximation fo r the quantum-well susceptibility. We compare results for various stra ined and unstrained systems.