793 nm抽运下的掺Tm3+碲酸盐玻璃的发光特性

研究了掺Tm^3 碲酸盐玻璃在793nm钛宝石激光器抽运下的发光特性，结果发现除常规的^3H4→^3H6的811nm荧光外，还存在很强的^1G4→H5的785nm二光子转换荧光以及较弱的710nm和677nm三光子上转换荧光。     

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     

Optical transitions and upconversion properties of Er^3＋-doped chloride tellurite glasses

Er^{3+}-doped lead chloride tellurite glasses were prepared using the conventional melting and quenching method. The absorption spectra were measured and the Judd－Ofelt analysis was performed. The spectroscopic parameters such as the intensity parameters, transition probabilities, radiative lifetimes, and branching ratios were obtained. Intense infrared emission and visible upconversion luminescence under 976 nm excitation were observed. For the 1.55μm emission, the full width at half maximum and the emission cross sections are more than 50 nm and 8×10^{- 20}cm^2, respectively. Three efficient visible luminescences centred at 525, 547, and 658nm are assigned to the transitions from the excited states {}^{2}H_{11/2}, {}^{4}S_{3/2}, and {}^{4}F_{9/2} to the ground state {}^{4}I_{15/2}, respectively. The upconversion mechanisms and the power-dependent intensities are also discussed and evaluated.     

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。     

低温下掺镱磷酸盐激光玻璃的光谱和激光特性

根据低温下测得的Yb^3 ：磷酸盐玻璃的吸收光谱和荧光光谱。计算了Yb^3 离子在磷酸盐玻璃中的能级结构，并解释了荧光寿命在低温下变化异常的原因。在低温下采用940nm的二极管激光器抽运Yb^3 ：磷酸盐玻璃获得了准连续激光输出，在热力学温度为8K时最大输出功率为2mW，斜率效率为4％，激光中心波长为1000m。     

OH~-对磷酸盐铒玻璃光谱性质的影响

本文系统研究了 Yb3 + 、Er3 + 共掺磷酸盐铒玻璃中 OH- 含量与铒玻璃荧光寿命和光谱性质的关系 .结果表明 OH- 基团的存在使得 Er3 + 离子的荧光强度显著降低 ,荧光寿命大大缩短 .比较了三种不同 Al2 O3 含量 ( 5mol% ,8mol%和 1 3 mol% )的铒玻璃在 2 .9μm波长处的红外吸收系数与铒离子荧光寿命的关系 ,发现玻璃中 OH- 在 2 .9μm的吸收系数和 Er3 +的4 I13 / 2 能级离子衰减速率成线性关系 ,不同 Al2 O3 含量的玻璃具有不同 Er3 + 和 OH- 基团的相互作用参量和不同的荧光寿命值及量子效率 .并从玻璃结构上解释了 Al2 O3 含量对除水机制和光谱性质的影响 .经过充分除水后的铒玻璃荧光寿命可达到 9.1 ms     

Investigation on Nonradiative Decay of the Er^3＋^4I13/2 → ^4I15/2 Transition in Different Tellurite Glass Matrix

Three kinds of Er^3＋-doped tellurite glasses with different hydroxyl groups are prepared by the conventional melt-quenching method. Infrared spectra are measured to estimate the exact content of OH^- groups in samples. The maximum phonon energy in glasses are obtained by measuring the Raman scattering spectra. The strength parameters Ωt （t = 2, 4, 6） for all the samples are calculated and compared. The nonradiative decay rate of the Er^3＋ ^4I13/2 → ^4I15/2 transition are calculated for the glass samples with different phonon energy and OH^- group contents. Finally, the effect of OH^- groups on fluorescence decay rate of Er^3＋ is analysed, the constant KOH-Er of TWN, TZPL and TZL glasses are calculated to be 9.2 × 10^-19 cm^4s^-1, 5.9 × 10^-19 cm^4s^-1, and 3.5 × 10^-19 cm^4s^-1, respectively.     

Structural and Upconversion Fluorescence Properties of Er^3＋／Yb^3＋-Codoped Lead-Free Germanium-Bismuth Glass

We study the structural and infrared-to-visible upconversion fluorescence properties of Er^3 /yb^3 -codoped leadfree germanium-bismuth glass. The structure of lead-free germanium-bismuth-lanthanum glass is investigated by peak-deconvolution of F~aman spectroscopy. Intense green and red emissions centred at 525, 546, and 657nm,corresponding to the transitions ^2H11/2 → 4I15/2, ^4S3/2 → 4I15/2, and 4F9/2 → 4I15/2, respectively, are observed at room temperature. The quadratic dependence of the 525, 546, and 657nm emissions on excitation power indicates that a two-photon absorption process occurs under 975nm excitation.     

Laser Characteristics of Cladding-Pumped Short Er^3＋/yb^3＋ Codoped Single Mode Phosphate Glass Fibre

We experimentally investigate the laser characteristics of a series of short pieces of newly-developed Er^3＋/ Yb^3＋ codoped single mode phosphate glass fibres via the cladding pump of a 976nm multimode laser diode. A stable continuous-wave single transverse mode laser with over 85 m W at 1553nm is generated from a 5.5-em-long active fibre. Single mode laser output power per unit length is up to 15 mW/cm. Moreover, the slope efficiency is 11.8% when the pump power is below 940mW and the 3dB linewidth is 0.06nm at the maximum pump power. The numerical simulation results show that the laser emission slope efficiency can exceed 20% by means of increasing the coupling efficiency of the pump to the fibre core further.     

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， 关键词： 锗碲酸盐玻璃 玻璃热稳定性 荧光