First principles calculations of structural, electronic and optical properties of Zn1−xBexSeyTe1−y quaternary alloys

The structural, electronic and optical properties of Zn1−xBexSeyTe1−y quaternary alloys are investigated using the full potential-linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT). We used both the Wu–Cohen and the Engel–Vosko generalized gradient approximations of the exchange-correlation energy that are based on the optimization of the total energy and the corresponding potential, respectively. Some basic physical properties, such as lattice constant, bulk modulus, electronic band structures, and optical properties (dielectric constant and refractive index) are calculated, nonlinear dependence on the compositions x and y are found. In addition, the energy band gap of zinc-blende Zn1−xBexSeyTe1−y quaternary alloys lattice matched to GaAs substrate is investigated. To our knowledge this is the first quantitative theoretical investigation on Zn1−xBexSeyTe1−y quaternary alloys and still awaits experimental confirmations.