((GeSe_2)(SnSe_2)_(0.5))_(100-x)Te_x系统硫系玻璃的光学性能及结构

硫系玻璃光纤具有优良的中远红外透过特性、抗酸性及良好的流变特性,在中远红外传感、高能激光传输、光谱学领域具有广泛的应用前景。采用熔融淬冷法制备了系列((GeSe2)(SnSe2)0.5)100-xTex(x=0,20,40)硫系玻璃样品,测试了玻璃样品的X射线衍射谱、差示扫描量热曲线、可见/近红外光谱、Fourier红外光谱、显微Raman光谱,对玻璃的物化性能及结构进行表征。分析并讨论了在Ge-Se-Sn玻璃系统中随着Te的引入,玻璃样品的成玻能力及物化性能和光学特性的变化。利用经典的Tauc方程计算了样品的光学带隙的变化,解释并讨论了Raman光谱的变化与玻璃结构变化之间的关系。研究表明:Te的引入增加了玻璃结构的复杂度,使得基团及化学键之间的竞争激烈,提高了玻璃的成玻性能及稳定性;随着Te含量的增加,短波及长波截止边均发生红移,光学带隙减小,其中,玻璃组分样品((GeSe2)(SnSe2)0.5)60Te40的稳定性最好,其特征温度(ΔT)为79℃,且具有良好的红外透过性能,其红外透过范围为1~17.50μm。     

Yb~(3+)/Ho~(3+)共掺Ge_(25)Ga_5S_(70)玻璃中红外发光特性

用熔融急冷法制备了系列Yb3+/Ho3+共掺Ge25Ga5S70硫系玻璃,测试了样品的吸收光谱以及980nm激光泵浦下中红外荧光光谱特性,用Judd–Ofelt理论计算分析了单掺Ho3+在Ge25Ga5S70玻璃中的强度参数Ωi(i=2,4,6)、自发辐射跃迁几率、荧光分支比和辐射寿命等光谱参数。研究了Yb3+/Ho3+共掺样品在980nm激光泵浦下获得的Ho3+:2.9μm中红外荧光光谱性质,表明Yb3+/Ho3+之间存在能量共振转移。当固定Yb3+掺杂浓度为0.5%(质量分数,下同),随着Ho3+掺杂浓度从0增加为0.7%,Yb3+:2F5/2能级寿命明显单调下降,说明Yb3+/Ho3+之间有效的能量传递主要来源于Yb3+:2F5/2能级向Ho3+:5I6能级的共振能量传递。运用Futchbauer-Ladenburg公式计算比较了不同掺杂浓度下Ho3+:5I6→5I7跃迁的受激发射截面。     

铝诱导晶化制备多晶硅薄膜研究进展

铝诱导晶化(AIC)技术制备多晶硅(Poly-Si)薄膜因处理温度低、退火时间短,且所制备的薄膜晶粒尺寸大而受到广泛关注。阐述了AIC法制备Poly-Si薄膜的交换机制,着重讨论了AIC过程中工艺条件对制备Poly-Si薄膜质量的影响,简单介绍了AIC制备的Poly-Si薄膜在太阳电池器件方面的研究现状,并指出提高AIC法制备的Po-ly-Si薄膜籽晶层及外延层质量以改善薄膜电池性能是今后的重点研究方向。     

Tm3+/Ho3+共掺硫卤玻璃的2.00μm荧光特性研究

通过真空熔融淬冷法制备了不同浓度Tm3+/Ho3+离子共掺的70GeS2-20In2S3-10CsI玻璃样品,分析了样品的热稳定性及拉曼光谱,测试了样品的吸收光谱以及808 nm激光泵浦下Ho3+:5I7→5I8辐射跃迁对应的2.00μm荧光光谱特性.结果表明:Tm3+离子掺杂浓度为0.25mol%时,随着Ho3+离子掺杂浓度从0.05mol%增加到0.125mol%,Tm3+离子在1.86μm的发光强度逐渐减弱,Ho3+离子2.00μm荧光明显增强,表明Tm3+/Ho3+离子之间存在有效的能量转移.     

掺Er3+氟铅硅酸盐玻璃的光谱性质和热稳定性研究

制备了掺Er^3 氟铅硅酸盐玻璃，研究了玻璃的物理性质、热稳定性、吸收光谱、荧光光谱和荧光寿命，应用McCumber理论，计算了能级^4I13／2→^4I15／2跃迁的吸收和受激发射截面．结果表明：以PbF2等分子替代PbO含量，样品密度、折射率、热稳定性、吸收截面和受激发射截面降低，但荧光半高宽和荧光寿命增加，对Er^3 离子在不同玻璃基质中带宽特性的比较发现，Er^3 掺杂50SiO2—50PbF2玻璃的带宽特性与碲酸盐和铋酸盐玻璃相当，大于磷酸盐，锗酸盐和硅酸盐玻璃，表明掺Er^3 氟铅硅酸盐玻璃可作为宽带光纤放大器的基质材料。     

Highly Er3+/Yb3+ Co-Doped Fluoroaluminate Glasses for Microchip Laser at 1.54 μm

A series of highly Er3 /Yb3 co-doped fluoroaluminate glasses were investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and up-conversion spectra were performed to examine the effect of concentration quenching on spectroscopic properties. In the glasses with Er3 concentrations below 10% (mol fraction), concentration quenching is low and the Er3 /Yb3 co-doped fluoroaluminate glasses gave stronger fluorescence of 1.54 μm from the 4I13/2→ 4I15/2 transition than those of Er3 singly-doped glasses. In the glass with Er3 concentrations above 10%, concentration quenching of 1.54 μm obviously occurs more than that of the Er3 singly-doped samples because of the back energy-transfer from Er3 to Yb3 . To obtain the highest emission efficiency at 1.54 μm, the optimum in mol fraction when the Er3 concentration is less than 10%.     

Upconversion Emission in Er^3＋ Doped Novel Bismuthate Glass

Novel Er3 -doped bismuth lead strontiam glass was fabricated and characterized, and the absorption spectrum and upconversion spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ωt (t=2, 4, 6) were found to be Ω2＝3.27×10-20 cm2, Ω4＝1.15×10-20 cm2, and Ω6＝0.38×10-20 cm2. The oscillator strength, the spontaneous transition probabilities, the fluorescence branching ratios, and excited state lifetimes were also measured and calculated. The upconversion emission intensity varies with the power of infrared excitation intensity. A plot of log Iup vs log IIR yields a straight line with slope 1.86, 1.88 and 1.85, corresponding to 525, 546, and 657 nm emission bands, respectively, which indicates that a two-photon process for the red and green emission.     

掺镱硼酸盐和磷酸盐激光玻璃的研究

制备了掺Yb∶硼酸盐和Yb∶磷酸盐玻璃 ,并研究了它们的玻璃物理性质和光谱性质。掺Yb∶磷酸盐玻璃的热机械性质优于掺Yb∶硼酸盐玻璃。掺Yb∶硼酸盐玻璃的受激发射截面和荧光寿命分别为 0 5 3× 10 -2 0 cm2 和 0 85ms。掺Yb∶磷酸盐玻璃的受激发射截面和荧光寿命分别为 0 4 5× 10 -2 0 cm2 和 1 8ms。作为激光材料 ,掺Yb∶磷酸盐玻璃的综合性能优于掺Yb∶硼酸盐玻璃。用钛宝石激光器抽运Yb∶硼酸盐玻璃实现 8mW准连续激光输出。用波长为 976nm ,6W的LD抽运Yb∶磷酸盐玻璃获得了 6 2mW的连续激光输出 ,其斜率效率为 4 4 %。     

掺Er3+碲锌铋酸盐玻璃光谱特性研究

制备了掺铒碲锌铋酸盐玻璃样品84.5TeO2-(15-x)ZnO-xBi2O3-0.5mol% Er2O3(TZB x=0,2,4,6,8,10mol%).测试和分析了玻璃样品的吸收光谱、荧光光谱和4I13/2能级寿命等参数.根据McCumber理论,计算了Er3 受激发射截面(σpeake=(6.31～8.57)×10-21cm2)、并测量了Er3 荧光半高度(FWHM=65～70nm).结果表明:适量Bi2O3(～6mol%)的引入,能较好地改善玻璃样品FWHM,σpeake,4I13/2能级寿命和量子效率等光谱参数.     

用于WDM系统的掺稀土玻璃光纤

作为新的光纤放大器增益介质，掺稀土玻璃光纤近年来在WDM传输系统中发展迅速。在介绍了玻璃光纤用作光纤放大器增益媒质优点的基础上，综述了目前掺稀土玻璃光纤研究的要点、种类、性能及其应用实例。