Fe doping-stabilized γ-Ga2O3 thin films with a high room temperature saturation magnetic moment†
Saturation magnetic moment (Msm) is a key evaluation parameter of diluted magnetic semiconductors (DMSs). The higher the Msm, the more widespread the applications of electron spin for non-volatile information manipulation and storage. In this paper, first-principles simulations predicted that cation-deficient γ-Ga2O3, having an intrinsic magnetic moment per formula unit cell of about 1 μB, is an inherent candidate to prepare DMS with high Msm. To activate the potential of its magnetism, Fe was introduced as a dopant. A thermostable Fe-doped γ-Ga2O3 thin film with high room temperature (RT) Msm of 5.73 μB/Fe was first obtained using the laser molecular beam epitaxy (L-MBE) technique. While combining theoretical calculations and experimental data, the main source of RT ferromagnetism could be ascribed to the strong ferromagnetic (FM) coupling between Fe ions, p–d orbital overlap of the Fe–O bond, and defects. Our results provide a feasible model for designing high-performance γ-Ga2O3-based DMSs.