[9p-Z04-1~20] 13.8 Optical properties and light-emitting devices

[9p-Z04-16] Luminescence properties of PrF₃-doped ZnO-Sb₂O₃-GeO₂ glass phosphors

〇(D)Seiya Nishimura¹, Yasushi Nanai², Shinji Koh¹, Shingo Fuchi¹ (1.Aoyama Gakuin Univ., 2.National Defense Academy)

Keywords:phosphor, near-infrared, rare-earth ions

We synthesized PrF₃-doped glass phosphors using a melt-quenching method and investigated the luminescence characteristics to determine its suitability as a wideband near-infrared light-source. Optical activation of Pr³⁺ ions in all samples was confirmed by absorption spectra. Broad PL spectra from 700 to 1100 nm with four PL peaks 730, 870, 930 and 1040 nm were observed by blue-LED excitation in all samples. The PL spectra originate from the ³P₀→³F₄, 1D₂→³F₂, ³P₀→¹G₄, and ¹D₂→³F₄ transitions of Pr³⁺ ions that overlap each other. With the increase in PrF₃ concentration, the integrated PL intensity around 1040 nm (¹D₂→³F₄) was sharply decreased compared to the other PL peaks. We discussed investigated the spectral change by PL and PL decay curve measurements for samples with different glass thickness and PrF₃ concentration and found that, regardless of the glass thickness, similar PL spectra were observed. While the fluorescence lifetime of PL peaks at 730, 870 and 930 nm slightly decreased with increasing PrF₃ concentration, a drastic decrease of the lifetime at 1040 nm was observed. These results demonstrate that the cross-relaxation phenomenon is a dominant factor in the luminescence properties of PrF₃-doped glass phosphor.