Accurate ab initio predictions of III-V direct-indirect band gap crossovers

We report the compositional dependence of the electronic band structure for a range of III-V alloys. Standard density functional theory is insufficient to mimic the electronic gap energies at different symmetry points of the Brillouin zone. The Heyd-Scuseria-Ernzerhof hybrid functional with screened exchange accurately reproduces the experimental band gaps and, more importantly, the alloy concentration of the direct-indirect gap crossovers for the III-V alloys studied here: AlGaAs, InAlAs, AlInP, InGaP, and GaAsP. (C) 2010 American Institute of Physics. [doi:10.1063/1.3485297]