First-Principles Calculations of Structural, Electronic and Optical Properties of Ternary Semiconductor Alloys ZAs (x) Sb1-x (Z = B, Al, Ga, In)

We have investigated the structural and electronic properties of the BAs (x) Sb (1-x) , AlAs (x) Sb (1-x) , GaAs (x) Sb (1-x) and InAs (x) Sb (1-x) semiconductor alloys using first-principles calculations under the virtual crystal approximation within both the density functional perturbation theory and the pseudopotential approach. In addition the optical properties have been calculated by using empirical methods. The ground state properties such as lattice constants, both bulk modulus and derivative of bulk modulus, energy gap, refractive index and optical dielectric constant have been calculated and discussed. The obtained results are in reasonable agreement with numerous experimental and theoretical data. The compositional dependence of the lattice constant, bulk modulus, energy gap and effective mass of electrons for ternary alloys show deviations from Vegard's law where our results are in agreement with the available data in the literature.