Gain Characteristics of Er^3＋-Doped Phosphate Glass Fibres

An erbium-doped phosphate glass fibre has been drawn by the rod-in-tube technique in our laboratory. The gain for the Er^3＋-doped phosphate glass fibre with different pump powers and with different input signal wavelengths is investigated. The 2.2-cm-long fibre, pumped by a single-mode 980-nm fibre-pigtailed laser diode, can provide a net gain per unit length greater than 1.SdB/cm. The pump threshold is about 50mW at the wavelength of 1534nm, and below 70roW at 1550nm. The gain linewidth of the Er^3＋-doped phosphate glass fibre is greater than 34 nm and can cover the C band in optical communication networks.     

对导质结激光器和发光二极管退化的评论

把异质结用在半导体激光器和高亮度发光二极管,大大地改善了器件的性能。然而,由于早期器件的寿命不稳定,可靠性便是主要关心的问题。现在,可靠的器件已经生产了,这是由于广泛地研究退化的原因和避免方法的结果。激光器的可靠性由两种基本因素来控制,即镜面损伤和内部形成非辐射中心。     

Broadband amplified spontaneous emission from Er^3＋ -doped single-mode tellurite fibre

This paper reports on the fabrication and characterization of a newly erbium-doped single-mode tellurite glass-fibre applicable for 1.5-μum optical amplifiers. A very broad erbium amplified spontaneous emission in the range 1450--1650nm from erbium-doped single-mode tellurite glass-fibre is obtained upon excitation of a 980-nm laser diode. The effects of the length of glass-fibre and the pumping power of laser diode on the amplified spontaneous emission are discussed. The result indicates that the tellurite glass-fibre is a promising candidate for designing fibre-optic amplifiers and lasers.     

用于S波段放大器的掺铥重金属氧化物玻璃发光性质研究

制备了不同Tm³⁺离子浓度的PbO-Bi₂O₃-Ga₂O₃-GeO₂重金属氧化物玻璃，根据吸收光谱计算了JO强度参量以及Tm³⁺离子在玻璃中的自发辐射概率、荧光分支比及荧光辐射寿命等光谱参数.通过测量1470nm波段发射光谱，计算表明该玻璃系统在S波段有较宽的荧光半高宽和较大的峰值受激发射截面，但玻璃中荧光寿命随稀土离子浓度增加呈线性下降，而交叉弛豫速率随浓度的平方迅速增加.研究结果仍可表明掺铥重金属氧化物玻璃是一种理想的S波段宽带光纤放大器用基质材料. 关键词： 重金属氧化物玻璃 3+离子')" href="#">Tm³⁺离子 S波段光纤放大器 光谱性质     

977nm抽运下掺铒碲酸盐基氧卤玻璃的光谱特性

研究了掺铒TeO2-ZnO-PbCl2碲酸盐基氧卤玻璃在977nm激光二极管抽运下的发光和上转换发光特性，结果发现除红外153μm4I13/2→４I15/2发光外（荧光半高宽高达69nm），该玻璃还存在很强的２Ｈ11/2→４I15/2（527nm），４Ｓ3/2→４I15/2（549nm）和４Ｆ９／２→４Ｉ１５／２（666nm）可见上转换发光.应用Judd-Ofelt理论计算得到玻璃强度参数Ωt（t=2，4，6）分别为Ω2=587×10-20cm2，Ω4=208×10-20cm2，Ω6=116×10-20cm2，计算了铒离子跃迁振子强度、自发辐射概率、荧光分支比、荧光寿命等光谱参量.应用McCumber理论计算得153μm处的玻璃受激发射截面可达875×10-21cm2实验结果表明，与硅酸盐玻璃、磷酸盐玻璃、氟化物玻璃等比较，掺铒碲酸盐基氧卤玻璃在宽带掺铒光纤放大器和上转换激光器中有着极大的研究和应用潜力. 关键词： 掺Er3+ 碲酸盐玻璃 氧卤玻璃 Judd-Ofelt理论 光谱性质     

Er^3＋/Yb^3＋ Codoped Phosphate Glass Fibre with Gain per Unit Length Greater Than 3.0 dB/cm

We experimentally study a novel fibre with high gain per unit length based on the homemade erbium-ytterbium codoped phosphate glass. The gain and noise characterizations with different pump powers at different wavelengths are investigated. The 1.8-cm-long fibre, dual-pumped by two single mode 980-nm fibre-pigtailed laser diodes, provides a gain per unit length greater than 3.0dB/cm and a noise figure less than 6.SdB. The gain saturation behaviour at 1535nm is obtained and the saturation output power （3 dB compression） is greater than 5 dBm.     

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。     

Upconversion properties of Er^3＋/Yb^3＋ co-doped TeO2-Nb2O5-Li2O glasses

The Er^3＋/Yb^3＋ co-doped TeO2-Nb2O5-Li2O glass is prepared by conventional melting method, and its upconversion spectra are measured. The intense green upconversion luminescence upon excitation with a 976 nm laser diode is observed with the naked eyes. The dependence of luminescence intensity on the ratio of Yb^3＋/Er^3＋ is discussed in detail, and the relationship between the ratio of green luminescence intensity to red luminescence intensity and the ratio of Yb^3＋/Er^3＋ is also studied, The luminescence intensity increases with the ratio of Yb^3＋/Er^3＋ increasing. The ratio of Yb^3＋/Er^3＋ plays a more important role than the concentration of Er^3＋ in determining the upconversion luminescence intensity. The ratio of green luminescence intensity to red luminescence intensity reaches a maximum when ratio of Yb^3＋/Er^3＋ is 3. Thus the glass could be one of the potential candidates for LD pumping solid-state lasers.     

Er3+/Yb3+共掺的氟磷酸盐玻璃的光谱性质和热稳定性

研究了Er3+/Yb3+共掺的氟磷酸盐玻璃的光谱性质和热稳定性。应用Judd-Ofelt理论计算了玻璃的三个强度参量Ωｔ (ｔ=2,4,6)，计算了Er3+离子的辐射跃迁几率，荧光支效率和自发辐射几率等光谱参量。 经荧光谱测试发现掺Er3+/Yb3+共掺的氟磷酸盐玻璃的荧光半高宽可达63nm ，应用McCumber理论计算了1.53μｍ处的受激发射截面，可达6.85×10-21 cm2。     

化学环境对掺过渡金属功能材料发光性能的影响

分析了掺过渡金属离子的发光功能材料的发光性能对化学环境变化的敏感性,由于源于过渡金属离子d电子没有像稀土离子f电子那样受到外层电子严格的屏蔽,所导致的声子-电子耦合强度大,因而就对母体材料化学环境更敏感。文章详细地介绍了化学结构类型、配位体间相连方式及其晶格半径对掺Mn2+发光材料发光性能的影响,分析晶体场强度参数(10Dq)对含Cr3+材料室温自发辐射4T2g→4A2g和激发态吸收4T2g→4T1g(4F)跃迁最大能量差的影响,探讨了共价性强弱对Os4+材料光谱性能的影响。说明了利用掺过渡金属的发光材料对母体材料的化学环境变化的敏感性对发光材料研发的指导意义,可以利用这种敏感性改善和优化材料设计,从而寻求具有更优异发光性能的发光材料。