Photoluminescent properties of near-infrared excited blue emission in Yb, Tm co-doped LaGaO3 phosphors

Abstract LaGaO 3 :Tm 3+ , Yb 3+ powder with different Yb 3+ contents (0–~0.15 mol) was synthesized by a conventional solid-state reaction. The structure, morphology and chemical analysis of the as-prepared phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques, respectively. The photoluminescence properties of the as-prepared powder samples were studied. The spectrum consisted of 1 G 4 → 3 H 6 , weak 1 G 4 → 3 F 4 , and intense 3 H 4 → 3 H 6 transition bands within the f 12 configuration of Tm 3+ , together with the 2 F 5/2 → 2 F 7/2 transition of Yb 3+ . Up-converted emission of LaGaO 3 :Tm 3+ , Yb 3+ powders was observed under laser diode excitation of 975 nm. Obvious differences in up-converted emission spectra among the as-obtained products were observed, and possible reasons were discussed. The corresponding up-conversion mechanism was also proposed.