First principles investigation of optical properties of zinc-blende AlxGa1-xAs1-yNy materials

We have performed a first-principle Full Potential Linearized Augmented Plane Waves calculation within the local density approximation (LDA) to the zinc-blende AlxGa1 - xAs1 - yNy to predict its optical properties as a function of N and Al mole fractions, The accurate calculations of electronic properties such as band structures and optical properties like refractive index, reflectivity and absorption coefficient of AlxGa1 - xAs and AlxGa1 - xAs1 - yNy with x <= 0.375 and y up to 4% are presented. AlxGa1 - xAs on GaAs have a lattice mismatch less than 0.16% and the lattice constant of AlxGa1 - xAs has a derivation parameter of 0.0113 +/- 0.0024. The band gap energies are calculated by LDA and the band anticrossing model using a matrix element of C-MN = 2.32 and a N level of E-N = (1.625 + 0.069x) eV. The results show that AlxGa1 - xAs can be very useful as a barrier layer in separate confinement heterostructure lasers and indicate that the best choice of x and y AlxGa1 - xAs1 - yNy could be an alternative to AlxGa1 - xAs when utilized as active layers in quantum well lasers and high-efficiency solar cell structures. (C) 2010 Elsevier B.V. All rights reserved.