The bulk crystal growth and yellow–orange spectral performances of Pr3+: BaF2 and Pr3+/RE3+(RE3+ = Gd3+, Y3+, Lu3+, Ce3+): BaF2 crystals

In this study, we synthesized Pr3+:BaF2 and Pr3+/RE3+ (RE = Gd, Y, Lu, Ce) co-doped BaF2 crystals, exploring their novel spectral properties through co-doping with Gd, Y, Lu, and Ce ions. The research demonstrates that both singly doped and co-doped BaF2 crystals have broader full width at half maximum (FWHM) values (24.82 nm) and longer fluorescence lifetimes (244 µs) than typical Pr3+-doped crystals, indicating their potential as gain media for Pr3+-based yellow–orange lasers. Notably, co-doping with Gd3+ enhances yellow–orange light emission up to 12 times, Y3+ up to 8 times, and Lu3+ up to 9 times. The effect is more pronounced with increased concentrations of co-dopants, while Ce3+ doping mainly expands the FWHM. Low-temperature spectral analysis confirms that co-doping alters the spectral performance by disrupting symmetric clusters in Pr: BaF2 crystals, forming new clusters with lower symmetry, and enhancing lattice distortion, thus increasing the absorption cross-section to 1.69 × 10−20 cm². Our findings highlight the significant potential of these crystals in biomedical, spectroscopic, information processing, atmospheric detection, and remote sensing applications.