Influence of Point Defect on the Electronic and Magnetic Properties of β‐Ga ₂ O ₃ : A First‐Principles Study

In this study, first‐principles calculations are employed to systematically explore the influence of Ga vacancy and substitutional doping with a series of 3 d metallic atoms X, including Ti, V, Cr, Mn, Fe, Co, Ni, and Cu, on the stability, geometric structure, electronic structure, and magnetic properties of β‐Ga 2 O 3 . We calculated the defect formation energy of Ga vacancy and substitutional 3 d metallic atoms X in β‐Ga 2 O 3 under O‐rich and Ga‐rich conditions, respectively. Our results demonstrate that Ga vacancy and X‐doped β‐Ga 2 O 3 systems are more facile to be synthesized in oxygen‐rich environment than in Ga‐rich environment. Additionally, β‐Ga 2 O 3 with Ga vacancy or Cu doping exhibits p ‐type semiconducting behavior. Importantly, the spin‐polarized state is stable in Ga vacancy and 3d metallic atoms X‐doped β‐Ga 2 O 3 systems. Specifically, Ga vacancy, Ti, V, Cu, Cr, Ni, Mn, Co, and Fe induce magnetic moments of 0.55, 1.83, 2.02, 2.96, 3.0, 4.0, 4.0, and 5.0 μ B , respectively. The magnetic moment mainly arises from dopant atom and relates to the hybridization between neighboring O atoms around vacancy or the dopant atom. This work not only identifies a potential new dilute magnetic semiconductor material for spintronic applications but also expands the application potential of gallium oxide.