ALattice parameters and band structure of ternary mixed crystals Al xGa1-xAs from first-principle calculations

Abstract

Lattice parameters and band structure of the ternary mixed crystal Al xGa1-xAs of zinc blende structure are calculated by first-principle calculations within the framework of the density functional theory. The results for the equilibrium lattice parameters and band gaps of AlxGa1-xAs for the Al-composition varying from 0.0 to 1.0 by step of 0.125 are presented and discussed. The results show that the lattice constants vary with the composition almost linearly following the Vegard's law. The electron band gap at Gamma; point exhibits non-linear behavior versus the composition. The Al-3s, 3p states shift to high energy region in the conduction band with increasing the Al concentration. It leads to an increase of the band gap and the blue shift phenomenon. © Published under licence by IOP Publishing Ltd.