Er3+掺杂新型GeS2-In2S3-CsI玻璃上转换光谱性质研究

用熔融淬冷法制备了掺Er³⁺的80GeS₂-10In2S₃-10CsI(mol%)硫卤玻璃样品,测试了样品的热学稳定性、喇曼光谱、吸收光谱以及上转换光谱,分析了Er³⁺离子在该玻璃中的上转换发光机理.应用Judd-Ofelt理论计算分析了Er3+离子在该样品中的强度参量Ωt(t=2,4,6)、自发辐射跃迁几率A、荧光分支比β以及辐射寿命τrad等光谱参量.在980 nm LD泵浦激发下,首次在该种玻璃中观察到强烈的绿光(526 nm、549 nm),分别对应于2H11/2→4I15/2和4S3/2→4I15/2的跃迁,其中549 nm处绿光较强.549 nm处上转换荧光寿命为0.34 ms,量子效率为69%.同时研究了绿光(526 nm、549 nm)上转换发光强度随泵浦激发功率的变化,其发光曲线拟合斜率分别为1.71和2.03,表明绿光是双光子吸收过程.研究结果表明：掺Er³⁺的80GeS₂-10In2S₃-10CsI硫卤玻璃是一种上转换绿光激光器的潜在基质材料.

Investigation on Upconversion Spectroscopic Properties of Er3+-doped Novel GeS2-In2S3-CsIGlass

Er³⁺-doped 80GeS₂-10In2S₃-10CsI(mol%)chalcohalide glass was fabricated by melt-quenching technique. The thermal stability, Raman spectra, absorption spectra, upconversion emission spectra of glass samples were measured, and upconversion mechanisms of Er3+ in the glass were analyzed. The intensity parameters(Ωt,t=2,4,6), spontaneous transition probabilities(Α), fluorescence branching ratios(β), and radiative lifetimes(τrad) were calculated by using the Judd-Ofelt theory. Under 980 nm diode laser excitation, intense emission bands centered at 526 nm and 549 nm corresponding to the transitions of 2H11/2→4I15/2 and 4S3/2→4I15/2 , respectively, were observed for the first time in this glass, and intensity of 549 nm green light is more stronger. For 549 nm emission band, the upconversion fluorescence lifetime is 0.34 ms, and the quantum efficiency is 69%. The dependence of visible emission intensities upon excitation intensity was examined. A plot of logIUP vs  logIIR yields two fitted lines with slope 1.71 and 2.03, respectively, which indicates a two-photon process for green emission. Results suggest that Er³⁺-doped 80GeS₂-10In2S₃-10CsI chalcohalide glass may be a potential host material for upconversion green lasers.