Preparation and Optical Properties of Er^(3+)-Doped Gadolinium Borosilicate Glasses

Er^(3+)-doped Gd_2O_3 -SiO_2 -B_2O_3 -Na_2O glasses were prepared, and formation range of glass of Gd_2O_3 -SiO_2 -B_2O_3 system was experimentally obtained. It is found that the glass phase can be formed only when the content of SiO_2 is 0～50%(molar fraction), Gd_2O_3 is 0～30%(molar fraction) and B_2O_3 is above 20%(molar fraction) in this glass system. The glass can also be obtained but becomes translucent at the contents of 60%(molar fraction) SiO_2 and 30% Gd_2O_3 , or at the contents of 60%(molar fraction) SiO_2 and 30%(molar fraction) B_2O_3. There is no glass phase formed in other glass components. Glass forming ability for Gd_2O_3 content of 10%, was characterized by the value of β, the parameter of crystallization tendency, which is 0.32～1.76, obtained from the differential thermal analysis. The absorption and emission cross section, the J-O parameters Ωt_((2,4,6)) and radiative transition probabilities were calculated by using the theory of McCumber and Judd-Ofelt. The emission properties at 1.5 μm of the samples are discussed with the product of full width at half maximum and stimulated emission cross section. It can be seen that the value of the FWHM×σ_e^(peak) product in the prepared glass is more than those of germanate, silicate and phosphate glasses. Furthermore, the maximum value of the product among these glasses reported in this work is close to that of oxyfluoride silicate glass. Therefore, the Er^(3+)-doped gadolinium borosilicate glass in this paper is a candidate for broadband erbium doped fiber amplifiers.

Up-conversion photoluminescence characteristics of Yb^(3+):Er^(3+):Tm^(3+) co-doped borosilicate glasses

Yb^3＋：Er^3＋：Tm^3＋co-doped borosilicate glasses are prepared. Their strong up-conversion photoluminescence spectra in a range from ultra-violet to near-infrared, which are excited by a 978-nm laser diode, are measured, and the mechanisms of energy transfer among Yb^3＋ Er^3＋ and Tm^3＋ ions are discussed. The results show that there is an unexpected wavelength at 900-nm emission from Yb^3＋ Stark splitting levels to pump Tm^3＋ ions and there exists an optimum pump power. The concentration of the Tm^3＋ dopant gives rise to a prominent effect on the intensity of visible and near-infrared emissions for the yb^3＋：Er^3＋：Tm^3＋ co-doped borosilicate glasses.

High Quantum Efficiency and High Concentration Erbium-Doped Silica Glasses Fabricated by Sintering Nanoporous Glasses

A new method was used to prepare erbium-doped high silica （SiO2 % 〉 96 % ） glasses by sintering nanoporous glasses. The concentration of erbium ions in high silica glasses can be considerably more than that in silica glasses prepared by using conventional methods. The fluorescence of 1532 nm has an FWHM （Full Wave at Half Maximum） of 50 nm, wider than 35 nm of EDSFA （erbium-doped silica fiber amplifer）, and hence the glass possesses potential application in broadband fiber amplifiers. The Judd-Ofelt theoretical analysis reflects that the quantum efficiency of this erbium-doped glass is about 0.78, although the erbium concentration in this glass （6 × 10^3） is about twenty times higher than that in silica glass. These excellent characteristics of Er-doped high silica glass will be conducive to its usage in optical amplifiers and microchip lasers.

Er^(3+)∶Yb^(3+)∶Tm^(3+)共掺硼硅酸盐玻璃光致发光温度特性和能级劈裂

高温固相烧结法制备了Er3+∶Yb3+∶Tm3+共掺硼硅酸盐玻璃.在978 nm半导体激光器抽运下,测量了样品在300～573 K下光致发光谱强度随温度的变化,讨论了室温时上转换绿光和红光等波段的光谱劈裂.分析了Er3+,Yb3+和Tm3+之间的能量传递机制.研究结果表明,当温度升高时,Er3+∶Yb3+∶Tm3+共掺硼硅酸盐玻璃的481 nm蓝光、517和534 nm绿光、以及657 nm红光等光致发光强度单调下降,在490 K时几乎消失.但900 nm左右的近红外光谱则随温度的升高而持续增强,而且其中心波长向短波方向移动.在室温时,光谱劈裂明显,高温时劈裂逐渐消失.

Er^(3+)掺杂硼硅酸盐玻璃的近红外发射特性研究

利用高温熔融法合成了掺Er3+硼硅酸盐玻璃。测量了样品的吸收光谱,由J-O理论得到了强度参数Ωλ(λ=2,4,6)及一些相关参数。用970nm光激发测量了10～300K之间的近红外发射光谱。利用McCumber理论拟合得到了1.53μm发射的受激发射截面,并与测量得到的发射光谱线形符合较好。由受激发射截面和发射光谱得到的半高全宽分别为59和56nm。利用能级简化模型讨论了样品的红外变温发射光谱,提出了增大1.53μm发射带宽的途径。

Ho^(3+)单掺杂及其与Yb^(3+)、Er^(3+)共掺杂硼硅酸盐玻璃上转换发光的光谱分析

采用高温固相烧结法制备了Ho^(3+)单掺杂、Ho^(3+)/Yb^(3+)共掺杂、Ho^(3+)/Er^(3+)共掺杂和Ho^(3+)/Yb^(3+)/Er^(3+)共掺杂等系列硼硅酸盐玻璃,测量了样品的激发光谱和发射光谱。结果表明:Ho^(3+)单掺杂样品的激发光谱与发射光谱的强度随其浓度增加而逐渐减弱,原因是高浓度掺杂导致Ho^(3+)离子产生猝灭效应;Ho^(3+)/Yb^(3+)共掺杂玻璃由于Yb^(3+)离子的敏化作用,光谱强度增强;Ho^(3+)/Yb^(3+)/Er^(3+)共掺杂样品中Ho^(3+)离子向Er^(3+)离子发生能量传递,Ho^(3+)离子的激发光谱和发射光谱强度均减弱。同时讨论了峰值波长为550nm宽带发射峰的发光机制。

Er^(3+)/Eu^(3+)及Yb^(3+)/Er^(3+)/Eu^(3+)共掺杂硼硅酸盐玻璃的上转换发光分析

采用高温固相烧结法制备了Er3+/Eu3+共掺杂和Yb3+/Er3+/Eu3+共掺杂系列硼硅酸盐玻璃样品。在978 nm半导体激光器抽运下,测量了样品的光致发光谱,分析了上转换机制。结果表明:随着Er3+浓度的增加,Eu3+的595 nm光谱强度增强;Eu3+的692 nm光谱强度随Yb3+浓度增加而增强,并明显强于595 nm光谱。Er3+/Eu3+、Yb3+/Eu3+之间的能量传递和合作上转换等机制导致Eu3+离子上转换发射。

Eu^(3+)掺杂SiO_2-Al_2O_3-B_2O_3玻璃制备及光谱性能研究

高温熔制了Eu3+掺杂SiO2-Al2O3-B2O3-MxOy(M=Li+,Na+,K+,Mg2+,Ca2+,Sr2+,RE3+)硼硅酸盐玻璃,测试了玻璃样品的发射光谱、激发光谱和透射光谱,研究了不同碱金属离子、碱土金属离子对该系统荧光性能的影响。利用发射光谱计算了Ω2,Ω4以及5D0到7F2,7F4的自发辐射几率和振子强度f(5D0→7F2),f(5D0→7F4)。结果表明,材料的发射能级为5D0→7F1(590 nm),5D0→7F2(617 nm),5D0→7F4(698 nm),而且材料的结构对称性越差,跃迁戒律打破地越彻底,荧光发射越强。

新型低密度短寿命铈单掺硼硅酸盐玻璃闪烁材料

硼硅酸盐玻璃在探测领域作为闪烁基质材料具有天然的优势。本研究基于应用需求制备了Ce^(3+)离子掺杂硼硅玻璃闪烁材料60B_(2)O_(3)‐6SiO_(2)‐3Al_(2)O_(3)‐5BaO‐15Na_(2)O‐10La_(2)O_(3)‐1Sb_(2)O_(3)。基于密度和FT‐IR光谱对玻璃的结构进行了分析,结果表明加入的Ce^(3+)离子作为网络修饰体存在。吸收光谱显示该材料紫外吸收边均低于400 nm、光学带隙缩短至2.93 eV,这些因素都有利于提升Ce^(3+)离子在基质材料中的发光特性。采用306 nm泵浦波长,该材料在372 nm处得到了最佳的发射光谱。光学碱度随着Ce^(3+)离子浓度的增加而增加(0.5392~0.5417)的现象与发射光谱的红移结果相吻合。荧光寿命短至24.39 ns,与其他Ce^(3+)离子掺杂玻璃闪烁材料相比具有明显的优势。这些优势为检测领域提供了一种新的材料选择。