Band structure and optical constants of GaAs1-xNx

The composition dependence of direct and indirect band gap energies, anti-symmetric gap, valence band width, refractive index and high-frequency and static dielectric constants has been investigated for GaAs1-xNx ternary semiconductor alloys with the zinc-blende crystal structure over the whole nitrogen concentration range (x from 0 to 1). The calculations are mainly based on the pseudopotential approach within the virtual crystal approximation. The variation of band-gaps versus nitrogen content show important bowing parameters. Trends in ionicity have been discussed in terms of the anti-symmetric gap. The alloy concentration dependence of the optical parameters of interest is found to be highly nonlinear.