First-principles study of zinc-blende BxAlyIn1−x−yN quaternary alloy: Alchemical mixing approximation approach

Abstract

Detailed first-principle calculations of properties in zinc blende quaternary alloy [Formula: see text] at various concentrations are investigated using density functional theory (DFT) within virtual crystal approximation (VCA) implemented in alchemical mixing approximation. The calculated bandgaps show direct transitions at [Formula: see text]–[Formula: see text] and indirect transitions at [Formula: see text]–[Formula: see text], which are opened by increasing boron concentration. The density of state (DOS) revealed upper valence band (VB1) domination by [Formula: see text]-states atoms, while [Formula: see text]-states dominate the lower valence band (VB2); also, the DOS shows the contribution of [Formula: see text]-states to the conduction band. The first critical point in the dielectric constant ranges between 0.07–4.47 eV and is due to the first threshold optical transitions in the energy bandgap. Calculated static dielectric function (DF) [Formula: see text] is between 5.15 and 10.35, an indication that small energy bandgaps yield large static DFs. The present results indicate [Formula: see text]-[Formula: see text] alloys are suitable candidates of deep ultraviolet light emitting diodes (LEDs), laser diodes (LDs) and modern solar cell since the concentrations [Formula: see text] and [Formula: see text] make the bandgap and lattice constant of [Formula: see text]-[Formula: see text] quaternary alloys tunable to desirable values.