Computation of electronic and optical properties of gaasnsb with 16 band k dot p model

Abstract

The electronic band structure (BS) and optical gain have been calculated for GaAs1−x−yNxSby/GaAs alloys by combining two Band Anticrossing (BAC) Models for Conduction Band and Valence Band i.e. CBAC and VBAC under k.p formalism. This mathematical model based on a 16 X 16 Hamiltonian matrix is used to compute the anticrossing interactions between the sub bands for variable Sb and N concentration in GaAsNSb/GaAs. The effect of Sb and N related impurity levels in GaAsNSb/GaAs on the band gap, carrier effective masses, spin-orbit splitting energy, band offsets and their ratios are also investigated. It has been shown that band gap shrinks by ~330 meV for Sb and N concentration of 5 and 1.9 at% respectively. The concentration dependent band gap reduction and the enhancement of spin-orbit splitting energy results in the origin of a Dso > Eg regime which forms the basis for the suppressing Auger recombination mechanisms in III– V LASERs. We have also investigated the variation of optical gain for different injected surface carrier densities and carrier confinement assists the optical gain to reach 1400/cm−1 near 1.2 eV window.