掺铒碲酸盐玻璃中的协作上转换能量转移  

Energy transfer via cooperative upconversion between Er^(3+) ions in a tellurite glass

作　　者：周亚训[1,2] 戴世勋[2] 周灵[2] 徐铁峰[2] 聂秋华[2] 黄尚廉[1] 

机构地区：[1]重庆大学光电技术及系统教育部重点实验室,重庆400044 [2]宁波大学信息科学与工程学院,宁波315211

出　　处：《物理学报》2009年第2期1261-1268,共8页Acta Physica Sinica

基　　金：浙江省自然科学基金(批准号:Y107070);宁波市自然科学基金(批准号:2006A610026);宁波大学王宽诚幸福基金资助的课题~~

摘　　要：研制了组分为TeO2-ZnO-Na2O(TZN)和TeO2-ZnO-La2O3(TZL)掺铒碲酸盐玻璃,测试了碲酸盐玻璃中Er3+离子4I13/2能级荧光特性.结果发现,在较高的Er3+离子掺杂浓度下,碲酸盐玻璃的荧光强度随着Er3+离子掺杂浓度的提高而减小.分析表明,对于除水处理后的碲酸盐玻璃样品,Er3+离子间的协作上转换引起的无辐射能量转移是导致荧光强度猝灭的主要因素.通过对测量到的归一化荧光强度衰减曲线的拟合,进一步得到了协作上转换能量转移系数CTZN=3.27×10-18cm3/s和CTZL=3.01×10-18cm3/s.同时,计算得到了Er3+离子临界浓度QTZN=11.2×1020cm-3和QTZL=11.8×1020cm-3,以及临界相互作用距离RTZN=0.597nm和RTZL=0.587nm.与报道的其他玻璃相比,研制的碲酸盐玻璃具有较好的稀土Er3+离子溶解性、较小的协作上转换能量转移速率,是一种比较理想的用于宽带放大的掺铒玻璃基质.Erbium-doped tellurite-based glasses with compositions of TeO2-ZnO-Na2O（TZN）and TeO2-ZnO-La2O3（TZL）are prepared, and fluorescence properties of Er^ 3＋ ： 4I 13/2 → ^4I 15/2 transition have been investigated as a function of erbium-doping concentration. It is found that fluorescence intensity decreases evidently with increasing erbium-doping concentration under higher doping, and it is mainly a result of concentration quenching effect in which energy migration takes place due to energy transfer via cooperative upconversion between Er^ 3＋ ions when the procedure of removing OH^ -1 by bubbling oxygen is adopted in melting glass. By fitting the rate equations of population to the normalised fluorescence decay curves, the coefficients of cooperative upconversion are obtained, and the values for the ^4I 13/2 are estimated to be C TZN =3.27×10^ -18 cm^3/s and C TZL =3.01×10^ -18 cm^3/s, respectively. Also, the critical concentration and the critical interaction distance are calculated, and the values for the TZN and TZL glasses are Q TZN =11.2×10^ 20 cm^ -3 and Q TZL =11.8×10^ 20 cm^ -3 , R TZN =0.597 nm and R TZL =0.587 nm, respectively. Compared with some other glasses reported, the tellurite glass prepared by us has a better rare-earth Er^ 3＋ ion solubility and a lower rate of energy transfer via cooperative upconversion, and may serve as good glass host for broadband fiber amplifiers.

关 键 词：碲酸盐玻璃 荧光特性 协作上转换能量转移 浓度猝灭 

分 类 号：TQ171.7[化学工程—玻璃工业]