Electronic and magnetic properties of N-N split substitution in GaAs: A hybrid density functional study

Abstract

Employing the first-principles combined with hybrid functional calculations, the electronic and magnetic properties of GaAs doped with a N 2 molecule are investigated in this work. We find that in Ga 32 As 31 (N 2 ) As the N-N split is able to saturate the dangling bond of Ga atom ,form sp 3 -like hybridization, and simultaneously supply an extra localized electron, leading to a magnetic ground state with a magnetic moment of ∼1µ B . This magnetic ground state is different from previously nonmagnetic results predicted by PBE functional, which results from the self-interaction error inherent in semi-local density functional theory. Moreover, the band gap of magnetic ground state of Ga 32 As 31 (N 2 ) As alloy decreases, which is relative to GaAs . Finally we discuss and explain why the magnetism is not discovered in previous experiments and theories. C 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.