Bi离子掺杂GeO2-Al2O3-M(M=Na2O，BaO，Y2O3)玻璃的光学性质

用高温熔融法制备了Bi离子掺杂浓度为1mol%的GeO-B₂O₃-Na₂O (GBNB)，GeO₂-Al₂O₃-Na₂O(GANB)，GeO₂-Al₂O₃-BaO(GABB)和GeO₂-Al₂O₃-Y₂O₃(GAYB)玻璃.测定了样品玻璃的差热曲线、吸收、发射光谱及荧光衰减曲线.实验发现GBNB，GANB，GAYB，GABB的吸收边带逐步发生红移.由于这些吸收边带是由Bi³⁺的6s²电子到Bi⁵⁺ 6s⁰空轨道的跃迁引起.因此推断GBNB，GANB，GAYB，GABB玻璃中Bi⁵⁺离子的含量逐步增加.在GABB，GAYB，GANB三个样品中观察到发光中心约1220nm超宽带荧光发射.荧光强度从GABB，GAYB，GANB逐步减弱，荧光半高宽和荧光寿命逐步变小.这些超宽带的荧光归属为Bi⁵⁺离子的发光所致.从吸收与荧光光谱的变化，推断在GeO₂-Al₂O₃玻璃中引入BaO，Y₂O₃组分有利于Bi⁵⁺离子的形成.讨论了BaO，Y₂O₃化学组分对Bi离子在玻璃中的价态影响的内在机理.关键词：5+离子')" href="#">Bi⁵⁺离子超宽带发光吸收带荧光寿命

Properties of Bi doped Al2O3-GeO2-M (M=Na2O, BaO, Y2O3) glasses

The GeO-B₂O₃-Na₂O (GBNB)，GeO₂-Al₂O₃-Na₂O(GANB), GeO₂-Al₂O₃-BaO(GABB)and GeO₂-Al₂O₃-Y₂O₃(GAYB) glasses doped with bismuth of 1mol% concentration were prepared by melting method and measurement of their DTA curves, absorption and emission spectra and fluorescence decay curves were carried out. It was found that the absorption edges of GBNB，GANB，GAYB，GABB were red-shifted. Since the absorption edges are ascribed to the charge transfer transition from Bi³⁺ 6s² to Bi⁵⁺ 6s⁰，we conclude that the content of Bi⁵⁺ in GBNB, GANB, GAYB, and GABB glasses increased gradually. Near infrared super-broadband emission of GANB, GABB and GAYB samples were observed to be center-peaked at ～1220nm. The fluorescence intensity, FWHM and emission lifetime of GABB，GAYB，GANB were reduced gradually. The super-broadband emissions may be due to the formation and fluorescence of Bi⁵⁺. It could be deduced from the absorption and emission spectra that the introductions of BaO and Y₂O₃ into GeO₂-Al₂O₃ glass were advantageous to the formation of Bi⁵⁺ in the glass. The mechanism of BaO and Y₂O₃ composition affecting the formation of Bi⁵⁺ in the GeO₂-Al₂O₃ glass is discussed.