荧光俘获效应对掺饵氧化物玻璃光谱性质的影响

测试了不同掺杂浓度和样品厚度下掺铒磷酸盐和碲酸盐玻璃的吸收光谱、荧光光谱和荧光寿 命,计算了Er³⁺离子在1.53 μm处的吸收截面(σ_a)、发射截面(σ _e)、自发辐射跃迁概率(A_rad)、辐射跃迁寿命(τ_rad) 、以及辐射跃迁量子效率(η)等光谱参数.讨论了荧光俘获效应对掺铒磷酸盐和碲酸盐玻璃 光谱性质及光谱参数的影响.结果表明即使在铒离子低掺杂浓度(0.1 mol% Er₂O ₃)下,荧光俘获效应也普遍存在于掺铒玻璃材料中,使得荧光寿命(τ_{f)和荧光半高宽(FWHM)随样品的厚度和铒离子掺杂浓度增加而增大,导致碲酸盐和磷酸 盐玻璃中τf分别增加11%—37％和6%—17%,FWHM分别增加15%—64%和11%—55% ,使得掺铒玻璃材料的放大品性参数(σe×FWHM) 也相应被估高.由于铒离子在 碲酸盐玻璃中在1.53 μm处吸收和发射截面重叠面积较大,加之铒离子在前者基质中的发射 截面高于后者,使得掺铒碲酸盐玻璃中的荧光俘获效应高于磷酸盐玻璃. 关键词：荧光俘获铒离子碲酸盐玻璃磷酸盐玻璃}     

荧光俘获效应对Er3+/Yb3+共掺杂碲钨酸盐玻璃光谱性质的影响

制备了掺杂浓度相同而厚度不同的Er^3 ／Yb^3 共掺杂碲钨酸盐玻璃样品,测量了样品的吸收光谱和970nmLD激发下的Er^3 离子1．5um发射的荧光光谱和荧光寿命,计算了Er^3 离子的发射截面,研究了荧光俘获效应对Er^3 离子1．5um发射的光谱性能的影响。结果表明,样品中Er^3 离子存在很强的荧光俘获效应,且荧光俘获效应随样品厚度的增加而增强。荧光俘获效应使测得的荧光寿命比计算的自发辐射寿命要长,随样品厚度的增加,Er^3 离子1．5um发射的荧光寿命增加;其荧光有效线宽△λeff与次峰值强度和主峰值强度的比值,Ⅰa/Ⅰp也增加,且△λeff与Ⅰa／Ⅰp存在很好的线性关系。首次提出采用Er^3 1．5um波段荧光谱的次峰值强度和主峰值强度的比值,Ⅰa／Ⅰp与从McCumber理论计算得到的次峰值发射截面和主峰值发射截面的比值(σea／σep)的差值或比值来判断基质中Er^3 1．5um波段荧光俘获效应强弱的方法。     

含铒碲酸盐玻璃的上转换荧光性质研究

在室温下,用804nm波长的半导体激光器作激发源,在TeO_2-PbO基掺铒碲酸盐玻璃中实现了中心波长分别为525nm,550nm和660nm的上转换发射.荧光强度与激发功率呈非线性关系.估测了PbO含量对上转换荧光相对强度的影响.     

掺铒铋酸盐玻璃的光谱性质研究

研究了掺铒铋酸盐玻璃的吸收和荧光光谱性质,应用Judd-Ofelt理论计算了玻璃的三个强度参量Ω     

荧光捕获效应对Yb3+磷酸盐玻璃光谱性质的影响

测试了不同掺杂浓度和不同厚度下Yb3+ 磷酸盐玻璃的吸收光谱、荧光光谱和荧光寿命 ,计算了积分吸收截面、吸收截面、受激发射截面、自发辐射寿命以及荧光有效线宽等光谱参数 ,讨论了荧光俘获效应对Yb3+ 磷酸盐玻璃光谱性质的影响 .结果表明荧光俘获效应随样品厚度和掺杂浓度的增加而增大 .由于荧光俘获效应的存在使得测量的Yb3+ 磷酸盐玻璃荧光寿命明显长于计算的荧光寿命 ,在 0 2mol%Yb2 O3低掺杂浓度下采用不同厚度 ( <4mm)的样品测量的荧光寿命之间误差为 3 0 %左右 ,高浓度 ( 6mol%Yb2 O3)掺杂下误差可达 43 % .荧光俘获还造成荧光谱线加宽 ,导致荧光有效线宽在低浓度 ( 0 2mol%Yb2 O3)时增加 14% ,在高掺杂浓度 ( 6mol%Yb2 O3)下增加 3 0 %以上     

掺铒碲酸盐玻璃的光谱性质和能量传递

测试了掺Er碲酸盐玻璃在974nmLD泵浦下的吸收光谱、荧光光谱和上转换光谱,应用McCumber理论计算了Er³⁺的受激发射截面,分析了碲酸盐玻璃中Er³⁺离子的上转换发光机制,研究了Yb³⁺离子对Er³⁺离子上转换发光强度的影响以及两者之间的能量传递特性。     

荧光捕获效应对Yb3+磷酸盐玻璃光谱性质的影响

测试了不同掺杂浓度和不同厚度下Yb³⁺磷酸盐玻璃的吸收光谱、荧光光谱和荧 光寿命,计算了积分吸收截面、吸收截面、受激发射截面、自发辐射寿命以及荧光有效线宽等光谱参数,讨论了荧光俘获效应对Yb³⁺磷酸盐玻璃光谱性质的影响.结果表明荧光俘 获效应随样品厚度和掺杂浓度的增加而增大.由于荧光俘获效应的存在使得测量的Yb^{3+磷酸盐玻璃荧光寿命明显长于计算的荧光寿命,在0.2mol%Yb₂O₃低掺 杂浓度下关键词：荧光俘获掺镱磷酸盐玻璃荧光光谱}     

GeO2含量对掺铒锗碲酸盐玻璃物性和光谱特性的影响

本文研究了x GeO2-(70-x)TeO2-5K2O-5Na2O-10Nb2O5-10ZnO-0.2Er2O3(x=0,10,25,50,70(摩尔百分数))玻璃的物性和光谱特性,讨论GeO2含量对锗碲酸盐玻璃物性和光谱特性的影响.研究发现:GeO2的加入提高了碲酸盐玻璃热稳定性,并且使玻璃的最大声子能量略微增加;随GeO2的增加,掺Er3+锗碲酸盐玻璃的Judd-Ofelt强度参量Ω2和Ω6逐渐增大,但玻璃受激发射截面有减小的趋势;由McCumber理论,计算了掺铒锗碲酸盐玻璃在1.53μm处最大受激发射截面为9.92×10-21cm2,Er3+离子4I13//2→4I15/2发射谱的最大荧光半高宽为52nm,同时,实验发现,在977nm LD抽运下,掺铒锗碲酸盐玻璃存在较强的荧光上转换现象,随GeO2含量的增加,上转换荧光强度呈降低的趋势.     

掺铒铋酸盐玻璃光谱性质的组分依赖性研究

通过测试掺铒铋酸盐玻璃43Bi2O3-xB2O3-（57-x）SiO2（x=10，20，30，40，50mol％）中Er^3＋离子的吸收光谱、荧光光谱、荧光寿命及荧光强度，结合Judd—Ofelt和McCumber理论，对玻璃中Er^3＋离子光谱性质随玻璃组分的依赖关系进行了系统研究．研究结果显示，掺铒铋酸盐玻璃具有较其它玻璃优异的光谱性质．随着玻璃中组分B2O3含量的增加，强度参量Ω6、荧光半高宽和能级^4I15／2→^4I13/2间自发辐射跃迁几率相应增加，而荧光寿命、荧光强度和受激发射峰值截面相应减小，带宽品质因子（σe^pcak×FWHM）在组分B2O3含量30mol％时达到最大．     

碱土金属离子对掺铒磷酸盐玻璃除水性质的影响

以掺铒磷酸盐玻璃中铒离子寿命随OH含量变化为依据,系统研究了碱土金属离子类型和含量对磷酸盐铒玻璃除水性质的影响。结果表明,采用通干燥O2和CCl4除水工艺可有效降低玻璃中OH含量,除水效果在通气的最初阶段最为明显,玻璃中OH含量降低速率随通气时间延长而减慢,最终趋于动态平衡。值得指出的是,在相同通气时间,磷酸盐铒玻璃的荧光寿命随碱土金属离子半径增大而减短。含有较高浓度碱土金属离子的磷酸盐铒玻璃具有较短的荧光寿命,并且在停止通气后熔体重新吸水的能力变大。     

WO3对掺铒碲酸盐玻璃光谱性质的影响

制备了掺铒碲钨酸盐玻璃(80-x)TeO2-(10 x)WO3-8BaO-2Na2O-O.5Er2O3(x=0,5,10,15,20)玻璃,研究了WO3对掺铒碲钨酸盐玻璃的光谱性质.研究发现:随着WO3含量的增加,Ω4,Ω6先增加后减小,受激发射截面也是先增加后减小,而Ω2的变化则相反.由McCumber理论计算了掺铒碲钨酸盐玻璃在1.5μm的受激发射截面,其最大受激发射截面为0.96×10-21 cm2,Er3 的4I13/2→4I15/12的跃迁发射荧光光谱的最大荧光半高宽为82 nm.同时,实验发现,在976 nm抽运下,掺铒碲酸盐玻璃存在较强的荧光上转换现象,随WO3含量的增加,上转换荧光强度呈降低的趋势.     

Mixed heavy metal effect on emission properties of Er~(3+)-doped borosilicate glasses

Er3+-doped heavy metal borosilicate glasses were prepared using conventional melting and quenching method. The emission spectra of 4I13/2 → 4I15/2 transition were observed upon excitation at 974 nm and the lifetime of 4I13/2 level of Er3+ was measured. Based on these data, the fluorescence properties of Er3+ are investigated on the emission and gain characteristics at the 1.5 μm bands. In particular, the effect of relative heavy metal content on fluorescence properties is discussed.     

Spectroscopic and lasing properties of Er3+:Yb3+-doped fluoride phosphate glasses

Er³⁺ emission and lasing properties at 1.5 μm were studied in fluoride phosphate glasses (FP20) with different doping concentrations as well as in a commercial phosphate glass (Kigre QX). Emission decay behaviour at 1 μm and 1.5 μm was examined with respect to energy transfer between ytterbium and erbium. Emission cross-sections were determined using the reciprocity and Füchtbauer–Ladenburg methods. Gain spectra were calculated for the glasses and related to differences in the tuning curves and lasing properties. The temperature rise due to the quantum defect was determined via the ratios of green upconversion luminescence for different pump powers. The results from the laser and tuning experiments indicate that the FP20 glass offers good possibilities in broadband amplification and the generation of ultrashort pulses. Received: 24 August 2000 / Revised version: 27 October 2000 / Published online: 7 February 2001     

Laser spectroscopic properties of Nd3+ -doped tellurite glasses

The stimulated emission cross-section σ and fluorescence lifetime for the 1.06 μm emission (⁴F_3/2 →⁴I_1/12) have been measured for a number of Nd-doped tellurite glasses. The measured value of σ ? 9 × 10^-20 cm ² for the tellurite glasses is to be compared with the value of 3.5 × 10^-20 cm ² for the ED-2 glass. Based on the measured spectroscopic parameters, an LED-pumped tellurite glass fiber laser is predicted to perform better than ED-2 glass, both in the longitudinal and transverse pumping configuration. The threshold for side-pumped tellurite glass laser can be comparable or even lower than that in Nd:YAG.     

碱金属和碱土金属氟化物对掺Er3+氟磷酸盐玻璃光谱性质的影响

研究了碱金属和碱土金属离子修饰的掺Er3+氟磷酸盐玻璃的光谱性质,讨论了碱金属和碱土金属对铒氟磷玻璃的吸收和发射截面、荧光半高宽,Judd-Ofelt强度参数和上转换发光强度等光谱性质的影响,并与一些传统氧化物玻璃系统进行了比较.研究表明碱金属K+和碱土金属Sr2+掺杂高的玻璃更适宜用作光放大器基质.含12mol%K+的氟磷玻璃展现出7.83×10-21cm2的高发射截面和最小的荧光上转换强度;含23mol%Sr2+的氟磷玻璃则有7.58×10-21cm2的高发射截面、65nm的荧光半高宽及8.6ms的长的上能级荧光寿命.     

Thermal stability and frequency up-conversion properties of Er3+-doped oxyfluoride tellurite glasses

The thermal properties of 68TeO2-15BaF2-5SrF2-10LaF3-2KF glass were measured by different temperature analysis (DTA). Up-conversion luminescence of Ers+ ion in the obtained glass was investigated.Mechanism of up-conversion emission was discussed. The result shows that the obtained oxyfluoride tellurite glass 68TeO2-15BaF2-5SrF2-10LaF3-2KF has a good thermal stability (△T = 153.6 ℃) and strong up-conversion green emissions around 527 nm and 549 nm and red emission at 660 nm. This glass can be a promising host material for up-conversion fiber lasers.     

Ce3+对Er3+/Yb3+共掺TeO2-WO3-ZnO玻璃发光性能的影响

在Er3+/Yb3+共掺TeO2-WO3-ZnO玻璃中引入Ce3+,研究了Ce3+对Er3+1.5μm发射性能及其上转换发光性能的影响.结果表明,随Ce3+浓度的增加Er3+1.5μm波段的荧光强度先增强后降低,优化的Ce3+掺杂浓度在2.07×1020/cm3左右;1.5μm波段的荧光寿命则随Ce3+浓度的增加有轻微降低,从3.4ms降到3.0ms,但Ce3+浓度的增加对1.5μm波段的荧光半高宽基本无影响;Er3+/Ce3+间的交叉弛豫Er3+(4I11/2+Ce3+(2F5/2→Er3+(4I13/2+Ce3+(2F7/2使玻璃的上转换发光强度大大降低,但在过高的Ce3+浓度下,Er3+/Ce3+间的另一交叉弛豫Er3+(4I13/2+Ge3+(2F5/2→Er3+(4I15/2+Ce3+(2F7/2则使Er3+4I13/2能级粒子数减少,导致1.5μm波段荧光强度和荧光寿命降低.     

Effect of concentration quenching on the spectroscopic properties of Er3+/Yb3+ co-doped AlF3-based glasses

A series of highly Er3+/Yb3+ co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and upconversion spectra have been performed to examine the effect of Er3+/Yb3+ concentration quenching on spectroscopic properties. In the glasses with Er3+ concentrations below 10 mol%, concentration quenching is very low and the Er3+/Yb3+ co-doped fluoroaluminate glasses have stronger fluorescence of 1.54 μm due to the 4I13/2 → 4I15/2 transition than that of Er3+ singly-doped glasses. As Er3+ concentrations above 10 mol% in the Er3+/Yb3+ co-doped samples, concentration quenching of 1.54 μm does obviously occur as a result of the back energy transfer from Er3+ to Yb3+. To obtain the highest emission efficiency at 1.54 μm, the optimum doping-concentration ratio of Er3+/Yb3+ was found to be approximately 1:1 in mol fraction when the Er3+ concentration is less than 10 mol%.     

Er3+离子掺杂钡镓锗玻璃上转换发光机理研究

研究了Er3+离子掺杂钡镓锗玻璃的吸收光谱、拉曼光谱和上转换光谱.分析了Er3+离子在钡镓锗玻璃中的上转换发光机理.结果表明:玻璃的最大声子能量为828cm-1,紫外截止波长为275nm.采用800nm和980nmLD激发玻璃样品,在室温下观察到强烈的上转换绿光和红光发射.随着Er3+离子浓度的增加,绿光发光强度先增加后减小,而红光发光强度呈单调递增趋势.能量分析表明:800nmLD激发产生的绿光主要源于Er3+离子4I13/2能级的激发态吸收过程;红光发射主要源于Er3+离子4I13/2能级与4I11/2能级之间的能量转移过程.980nmLD激发产生的绿光主要源于Er3+离子4I11/2能级之间的能量转移过程;而红光发射主要源于Er3+离子4I13/2能级与4I11/2能级之间的能量转移过程和4I13/2能级的激发态吸收过程.通过量子效率分析,发现采用800nmLD激发Er3+离子掺杂浓度为1mol% 的样品时,上转换绿光发光效率最高.