Electronic transport in dilute GaAs:N

Plane-wave pseudopotential-based DFT (density functional theory) are used to determine the electronic properties (band structure, effective mass and energy gap) of dilute GaAs:N with substitutional nitrogen concentration $x=1-3 \%$.Calculations are performed using LDA (local density approximation) for the exchange-correlation functional and applied to large supercells (more than 64 atoms) to achieve the dilute limit. Scattering cross-section, as well as the mobility are derived from the nitrogen concentration dependence of the band gap in GaAsN. The effects of an N$_2$ split interstitial substitution on the electronic properties are also discussed. Finally, the presence of a localized nitrogen state in such material is also studied within this ab initio framework.