The electronic and magnetic properties of native point defects, including vacancies (V-Ga and V-S), antisites (Ga-S and S-Ga) and interstitials (Ga-i and S-i) in monolayer and bulk GaS, were systemically studied using the density functional theory method. For the monolayer, the impurity states appeared in the band gaps of all defect structures except interstitial S-i. Half-metallic behavior can be obtained in the presence of V-Ga and Ga-i. Monolayers with V-Ga, Ga-S, S-Ga and Ga-i had a total magnetic moment of 1.0 mu(B), as did the bulk samples with V-Ga, Ga-S and S-Ga, whereas the monolayers with V-S and S-i and bulk sample with Ga-i were spin-unpolarized. In addition, n- and p-type GaS monolayers were obtained under Ga-rich and S-rich conditions, respectively. Ga-S and S-Ga were identified as suitable n- and p-type defects, respectively.
展开▼
