共查询到19条相似文献,搜索用时 109 毫秒
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通过高温熔融法和热处理制备了含有-γBi2WO6纳米晶的Er3+掺杂透明硼铋酸盐微晶玻璃.根据X射线粉末衍射结果和Scherrer公式计算得到-γBi2WO6晶粒大小约为15 nm.由于部分Er3+离子取代Bi3+进入-γBi2WO6纳米晶相中,使得Er3+离子在1.5μm的有效发射带宽由78 nm增加到85 nm,同时Er3+离子在4I13/2能级的荧光寿命由0.67 ms增加到1.43 ms.此外,与原始玻璃相比,在Er3+掺杂硼铋酸盐微晶玻璃中观察到强烈的绿光上转换发光,其上转换发光机制可以归为双光子过程. 相似文献
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掺铒氧氟碲酸盐玻璃的上转换发光研究 总被引:3,自引:0,他引:3
研究了掺铒氧氟碲酸盐玻璃的吸收光谱和上转换发光光谱,分析了Er^3 离子在氧氟碲酸盐玻璃中的上转换发光机理.结果表明:通过975nm的激光二极管(LD)激发,在室温下同时观察到强烈的绿光(524和545nm)和红光(655nm),分别是由于Er^3 离子^2H11/2→I15/2,^4S3/2→I15/2,和^4F9/2→I15/2跃迁.随PbF2含量增加,绿光的发光强度增加趋势较小,而红光的发光强度增加趋势大于绿光.上转换发光机理主要涉及能量转移和激发态吸收,强烈的绿光和红光激发都是由于双光子吸收过程. 相似文献
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研究了掺Er3+碲酸盐玻璃的吸收和荧光光谱性质;应用Judd-Ofelt理论计算了碲酸盐玻璃中Er3+离子的强度参数Ω(Ω2=4.79 × 10-20cm2,Ω4=1.52×10-20cm2,Ω6=0.66×10-20cm2),计算了离子的自发跃迁几率,荧光分支比;应用McCumber理论计算了Er3+的受激发射截面(σe=10.40 × 10-21cm2)、Er3+离子4I13/2→4I15/2发射谱的荧光半高宽(FWHM=65.5nm)及各能级的荧光寿命(4I13/2能级τrad=3.99ms);比较了不同基质玻璃中Er3+离子的光谱特性,结果表明掺铒碲酸盐玻璃更适合于掺Er3+光纤放大器实现宽带和高增益放大. 相似文献
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在980nm激发下,研究了Er3+、Yb3+和Tb3+单掺或共掺氟氧锗酸盐玻璃的上转换发光性质和机理.室温下,观察到了强的绿色和红色上转换发光,其发光中心位于524、546和658nm处,分别对应于Tb3+离子的5D4→7FJ(J=5和0)和Er3+离子的(2H11/2、4S3/2和4F9/2)→4I15/2跃迁.研究了TbF3、YbF3掺杂浓度以及激光功率对上转换发光强度的影响,讨论了Er3+、Yb3+和Tb3+之间的能量传递和上转换机理. 相似文献
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掺镝的氟锆酸盐玻璃的光谱 总被引:1,自引:0,他引:1
测量了氟锆酸盐玻璃中Dy3+离子的吸收光谱和荧光光谱,得到了Dy3+离子的J-O参量Ωt,Ω2=3.29×10 20cm2,Ω4=1.56×10 20cm2,Ω6=2.48×10 20cm2.计算了氟锆酸盐玻璃中Dy3+离子的发射特性,Dy3+离子1.3μm发射的6F11/2(6H9/2)→6H15/2跃迁的发射截面σe=0.62×10-20cm2.研究了Dy3+离子浓度对其荧光强度的影响,当Dy3+离子掺杂浓度(摩尔分数)超过1.5%时,发生了浓度淬灭效应. 相似文献
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掺铒碲酸盐玻璃的热力学稳定性和光谱性质的研究 总被引:1,自引:0,他引:1
分析了掺Er3+碲酸盐玻璃的热力学稳定性能,研究了掺Er3+碲酸盐玻璃的吸收和荧光光谱性质;应用Judd-Ofelt理论计算了碲酸盐玻璃中Er3+离子的强度参数Ω(Ω2=4.79×10-20cm2, Ω4=1.52×10-20cm2,Ω6=0.66×10-20cm2),计算了离子的自发跃迁几率,荧光分支比;应用McCumber理论计算了Er3+的受激发射截面(σe=10.40×10-21cm2)、Er3+离子4I13/2→4I15/2 发射谱的荧光半高宽(FWHM=65.5nm)及各能级的荧光寿命(4I13/2能级为τrad=3.99ms);比较了不同基质玻璃中Er3+离子的光谱特性,结果表明掺铒碲酸盐玻璃更适合于掺Er3+光纤放大器实现宽带和高增益放大. 相似文献
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研究Er3+掺杂镉铝硅酸盐玻璃的荧光光谱,比较以488nm、532nm和800nm激光泵浦样品产生的1534nm近红外光发射强度,利用Dexter能量转移理论分析Er3+离子浓度变化对荧光特性影响原因。 相似文献
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掺铒铋酸盐玻璃光谱性质的混合形成体效应 总被引:3,自引:0,他引:3
测得了Er3+离子在铋酸盐玻璃系列(50~75)Bi2O3-(20~45)B2O3-5Na2O,70Bi2O3-(17~25)B2O3-xZrF4-5Na2O,70Bi2O3-(0~25)B2O3-(0~25)SiO2-5Na2O中的吸收光谱、荧光光谱及4I13/2能级荧光寿命.提出并研究了Er3+离子光谱性质的混合形成体效应,结果表明Er3+离子在铋酸盐玻璃中通过混合形成体效应可以获得较大的有效线宽(△λeff=62~80nm)、较高的受激发射截面(σe=0.76~0.84×10-20cm2)、较宽的荧光半高宽(FWHM=55~80nm)以及较长的荧光寿命(τm=1.6~4.3ms),说明掺Er3+铋酸盐玻璃是光纤放大器实现宽带和高增益放大较为理想的基质材料. 相似文献
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Gd3+-Tb3+能量转移与Tb3+自敏化效应对重金属锗酸盐玻璃发光性能的影响 总被引:3,自引:0,他引:3
研究了一组Tb^3 掺杂重金属锗酸盐玻璃的发光特性。玻璃样品的X射线激发发射光谱结果显示,玻璃基质中由Gd^3 离子向发光中心Tb^3 的能量转移机制以及在一定浓度范围内Tb^3 之间的交叉弛豫过程对玻璃的发光性能有重要影响。前者表现在Gd^3 紫外发射光的减弱及Tb^3 绿发射光的增强,后者则显示Tb^3 在一定浓度范围内所特有的自敏化效应,使其蓝发射光减弱、绿发射光增强。第3种稀土离子La^3 的引入对发光中心Tb^3 离子具有分离效应,使Tb^3 之间的交叉弛豫概率降低,蓝发射光增强。 相似文献
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氟氧化物中Er3+的上转换发光 总被引:1,自引:0,他引:1
研究了Er^3 离子氟氧化物上的转换发光。在980nm光的激发下,测定了Er^3 离子浓度(分别为1mol%、2mol%、3mol%)不同时材料上的转换发光光谱。在可见光范围内,观察到了强红光和绿光,并且在短波段也观察到了光的发射,波峰分别位于661.545、456、409和380nm处。还测量了各样品的上转换发光强度随激发强度的变化情况,由LogIvis-LogIin曲线可知,红光为双光子过程和三光子过程,绿光为三光子过程。并初步研究了此材料的上转换过程和上转换通道。 相似文献
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Neodymium doped cadmium alkali borate glasses having composition 20CdO20R2O59.5H3BO30.5Nd2O3; (R = Li, Na and K) were prepared by conventional melt-quenching technique. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. The physical properties such as density, refractive index, molar volume, rare earth ion concentration etc. were determined. Optical absorption and fluorescence spectra were recorded. The Judd-Ofelt theory was applied on the optical absorption spectra of the glasses to evaluate the three phenomenological intensity parameters Ω2, Ω4 and Ω6. These parameters were in turn used to predict the radiative properties such as the radiative transition probability (A), radiative lifetime (τR) and branching ratio (βR) for the fluorescent levels of Nd3+ ion in the present glass series. The lasing efficiency of the prepared glasses has been characterized by the spectroscopic quality factor (Ω4/Ω6), the value of which is in the range of 0.2–1.5, typical for Nd3+ in different laser hosts. The variation of Ω2 with the change in alkali oxide has been attributed to the changes in the asymmetry of the ligand field at the rare earth ion site. The shift of the hypersensitive bands, study of the oscillator strengths and the variation of the spectral profile of the transition 4I9/2 → 4F7/2 + 4S3/2 indicate a maximum covalency of NdO bond for glass with potassium ions. From the fluorescence spectra, peak wavelength (λp), effective line widths (Δλeff) and stimulated emission cross-section (σp) have been obtained for the three transitions 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 of Nd3+ ion. The relatively high values of σp obtained for Nd3+ in present glass system suggest that these materials can be considered as suitable candidates for laser applications. The glass with potassium ions shows the highest value of the stimulated emission cross-section. 相似文献
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采用溶胶-凝胶法(sol—gel)制备掺0-20mol%Er^3 勃姆石(γ-AlOOH)凝胶,X射线衍射和差热分析法研究掺Er^3 :γ—AlOOH凝胶在950-1400℃烧结的相变过程.结果表明:Er^3 的掺杂降低α相的生长速度,抑制Al2O3的θ→α相变,推迟相变结束温度50-70℃,Er-Al-O系化合物Al10Er6O24和ErAlO3相的析出取决于掺Er^3 浓度和烧结温度.在较高烧结温度下,ErAlO3相由掺1-5mol%Er^3 :Al2O3中析出;Al10Er6O24相则在掺5-20mol%Er^3 :Al2O3中析出,随着烧结温度的升高,在全部掺Er^3 :Al2O3中析出.ErAlO3相促进θ→α相变的形核,α相形核起始温度可提前30-50℃,但对α相生长影响不大.Al10Er6O24相对θ→α相变没有显著影响. 相似文献
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计算了在Er3+/Yb3+共掺的硅酸盐、锗酸盐、磷酸盐和氟化物这四种玻璃基质中施主离子归一化荧光线形函数与受主离子归一化吸收线形函数的重叠积分,交叉弛豫几率.通过求解能级跃迁速率方程,得出4S3/2能级的相对布居数.定义了上转换发光效率可以用自发辐射跃迁几率A61和4S3/2能级的相对布居数之积来表征.分析了由于氟化物中4S3/2能级的无辐射跃迁几率较小而自发辐射跃迁几率较大,因此4S3/2能级有较大的相对布居数,在四种Er3+/Yb3+共掺的玻璃中,氟化物具有较好的上转换发光效率. 相似文献
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L. JyothiV. Venkatramu P. BabuC.K. Jayasankar M. BettinelliG. Mariotto A. Speghini 《Optical Materials》2011,33(6):928-936
The spectroscopic properties of tellurite glasses of composition (in mol%) TNKNd: (70 − x)TeO2-15Nb2O5-15K2O-xNd2O3 (x = 0.1, 1.0, 1.5, 2.0 and 2.5) and TNLNd10: 69TeO2-15Nb2O5-15Li2O-1.0Nd2O3 and lithium metaborate glass of composition LBNNd10: 89LiBO2-10Nb2O5-1.0Nd2O3 have been investigated using absorption and emission spectra and decay curve analysis. An energy level analysis has been carried out considering the experimental energy positions of the absorption and emission bands, using the free-ion Hamiltonian model. The spectral intensities have been calculated by using the Judd-Ofelt theory and in turn the radiative properties such as radiative transition probabilities, emission cross-sections, branching ratios and radiative lifetimes have been estimated. The decay curves at the lower concentrations are exponential while they show a non-exponential behavior at higher concentrations (?1.0 mol%) due to energy transfer processes. The effective lifetimes for the 4F3/2 level are found to decrease with increase in Nd2O3 concentration for all the glasses under investigation. The non-exponential decay curves have been well-fitted to the Yokota-Tanimoto model with S = 6, indicating that the nature of energy transfer is of dipole-dipole type and energy migration also plays an important role. The results obtained have been compared with Nd3+-doped phosphate, fluorophosphate, lead borate, tellurite, germanate and silicate glasses and Nd3+-doped YAG ceramic and Ca2Nb2O7 crystals. 相似文献
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Since infrared spectroscopy and density are advantageous tools for the investigations of glasses, we have used them to obtain information concerning the local structure of xGd2O3·(100 − x)[4Bi2O3·GeO2] glass system, with 0 ≤ x ≤ 30 mol%. Gd2O3 play the network modifier role in the studied glasses and determines, by progressive addition, the increase of structural volume difference between the hypothetical crystalline compounds and the quenched samples. FTIR spectroscopy data show that the glass structure consists on the BiO6, GeO4 and GeO6 structural units, and the conversion among these units mainly depends on the Gd2O3 content. 相似文献
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Tungsten based phosphate glasses are interesting non-crystalline materials, commonly known for photochromic and electrochromic effects, but also promising hosts for luminescent trivalent rare earth ions. Despite very few reports in the literature, association of the host́s functionalities with the efficient emissions of the dopant ions in the visible and near-infrared spectra could lead to novel applications. This work reports the preparation and characterization of glasses with the new composition 4(Sb2O3)96−x(50WO3 50NaPO3)xEu2O3 where x = 0, 0.1, 0.25, 0.5 and 1.0 mol%, obtained by the melt quenching technique. The glasses present large density (∼4.6 g cm−3), high glass transition temperature (∼480 °C) and high thermal stability against crystallization. Upon excitation at 464 nm, the characteristic emissions of Eu3+ ions in the red spectral region are observed with high intensity. The Judd–Ofelt intensity parameters Ω2 = 6.86 × 10−20, Ω4 = 3.22 × 10−20 and Ω6 = 8.2 × 10−20 cm2 were calculated from the emission spectra and found to be higher than those reported for other phosphate glass compositions. An average excited state lifetime value of 1.2 ms, was determined by fitting the luminescence decay curves with single exponential functions and it is comparable or higher than those of other oxide glasses. 相似文献
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用高温熔融工艺制备了四种不同Nd3+掺杂浓度的镉铝硅酸盐玻璃样品,以纳秒Nd:YAG调Q激光器为光源,采用z-扫描技术研究了它们的非线性光学特性。结果表明,随着Nd3+浓度的增加,样品的非线性折射系数和非线性吸收系数也增加;光限幅测量表明,当入射功率密度大于118mW/mm2时,样品的透射功率密度与入射功率密度不再呈线性增加关系,而是随着入射功率密度的增加,透过率逐渐降低,透射功率密度增加缓慢,随着Nd3+浓度的增加,其光限幅效应显著增强。分析表明其光限幅效应是由反饱和吸收过程所致。 相似文献