Fe doping-stabilized γ-Ga2O3 thin films with a high room temperature saturation magnetic moment

Saturation magnetic moment (M-sm) is a key evaluation parameter of diluted magnetic semiconductors (DMSs). The higher the M-sm, 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 gamma-Ga2O3, having an intrinsic magnetic moment per formula unit cell of about 1 mu(B), is an inherent candidate to prepare DMS with high M-sm. To activate the potential of its magnetism, Fe was introduced as a dopant. A thermostable Fe-doped gamma-Ga2O3 thin film with high room temperature (RT) M-sm of 5.73 mu(B)/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 gamma-Ga2O3-based DMSs.