CALCULATION OF GAIN-CURRENT CHARACTERISTICS IN ZNCDSE-ZNSE QUANTUM-WELL STRUCTURES INCLUDING MANY-BODY EFFECTS

The gain-spontaneous recombination characteristics have been calculate d for a 40 Angstrom Zn0.8Cd0.2Se-ZnSe quantum well including many body effects. We examine the effect of the inclusion of the Coulomb enhanc ement on the gain spectra and the gain-current relationship. We show t hat, in the absence of the Coulomb enhancement, the threshold current density of a 340 mu m 40 Angstrom Zn0.8Cd0.2Se-ZnSe quantum well laser is underestimated by approximately 40% and the lasing wavelength over estimated by 4 nm. Our calculation of the scattering lifetime for the first electron-heavy hole transition gives a lifetime varying between 29 and 37 fs, and shows that the carrier-phonon scattering mechanism i n II-VI quantum wells is more dominant than in III-V materials. We als o comment on the effect the neglect of Coulomb enhancement has on the calculation of leakage currents in a laser at threshold. (C) 1995 Amer ican Institute of Physics.