Designing luminescent centers in β -Ga 2 O 3 via lanthanide doping: a first-principles investigation

Abstract β -Ga 2 O 3 , an ultra-wide bandgap semiconductor, shows promise for high-power and optoelectronic applications but faces challenges in p-type conductivity and limited luminescence. Lanthanide (Ln) doping is explored to enhance functionality via sharp 4 f transitions. This study systematically investigates Ln-doped β -Ga 2 O 3 using first-principles calculations and effective Hamiltonian models to elucidate the electronic and optical properties induced by Ln incorporation. Results indicate a strong preference for Ln substitution at octahedrally coordinated Ga sites, with formation energies lower than at tetrahedral sites. Ce doping exhibits shallow donor behavior near the conduction band, while most Ln dopants remain neutral across the bandgap. Crystal field effects cause significant 4 f -level splitting, which could influence emission profiles. These findings provide critical insights for optimizing Ln-doped β -Ga 2 O 3 in advanced optoelectronics and quantum devices.