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1.
Effects of Nb2O5 on thermal stability and optical properties of Er3+-doped tellurite glasses 下载免费PDF全文
Er3+-doped tellurite glasses with molar compositions of
xNb2O5-(14.7-x)Na2O--10ZnO--5K2O--10GeO2--
60TeO2--0.3Er2O3
(x=0, 3, 5, 7 and 9) have been investigated for developing 1.5~μm
fibre and planar amplifiers. The effects of Nb2O5 on the thermal stability
and optical properties of Er3+-doped tellurite glasses have been discussed.
It is noted that the incorporation of Nb2O5 (x=5) increases the thermal
stability of tellurite glasses significantly. Er3+-doped niobium tellurite
glasses exhibit a large stimulated emission cross-section (7.2\times 10-21-
10.7×10-21~cm2 and the gain bandwidth, FWHM×\sigmae^{\rm peak} (274\times 10-28 - 480×10-28~cm3), which are
significantly higher than that of silicate and phosphate glasses. In addition, the
intensity of upconversion luminescence of the Er3+-doped niobium tellurite
glasses decreases rapidly with increasing Nb2O5 content. As a result,
Er3+-doped niobium tellurite glasses might be a potential candidate for
developing laser or optical amplifier devices. 相似文献
2.
Laser-diode excited intense upconversion luminescence of Er^3+ in bismuth-lead-germanate glasses 下载免费PDF全文
We have investigated infrared-to-visible upconversion luminescence of Er^3+ in bismuth-lead-germanate glasses. The UV cutoff wavelength is shortened while its lifetime is increased almost linearly, with PbF2 substituting for PbO in the bismuth-lead germanate glasses. Three emissions centred at around 529, 545 and 657 nm are clearly observed, which are identified as originating from the ^2H11/2→^4 I15/2,^4S3/2→^4 I15/2 and ^4 F9/2 →^4 I15/2 transitions, respectively. It is noted that all the upconversion emission intensities increase with PbF2 concentration increasing. The ratio between the intensities of red and green emissions increases with the increasing of PbF2 content. Energy transfer processes and nonradiative phonon-assisted decays account for the populations of the ^2 H11/2,^4 S3/2 and ^4F 9/2 levels. The quadratic dependence of fluorescence on excitation laser power confirms a two-photon process to contribute to the upconversion emissions. 相似文献
3.
研究了能量接受离子Ce3+对Er3+上转换发光强度以及Er3+在1.5 μm附近波段发光性能参数的影响,并从能量匹配及能级结构角度出发对Er3+/Ce3+间的能量转移机制进行了分析.分析认为,4 I11/2能级的Er3+通过无辐射能量转移把能量传递给2F5/2能级的Ce3+激发其跃迁至2F7/2能级,而4I11/2能级上的Er3+则无辐射弛豫至4I13/2能级,从而有效降低氟磷酸盐玻璃中Er3+的上转换发光.当Er3+浓度为1.11×1020 cm-3时,Ce3+的最佳掺杂浓度为2.22×1020 cm-3,此时Ce3+的引入不仅可以降低上转换发光,而且有助于提高Er3+在1.5 μm附近波段的荧光强度、发射截面以及4I13/2能级荧光寿命. 相似文献
4.
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.
关键词:
氟磷酸盐玻璃
光谱性质
Judd-Ofelt参数
光学放大器 相似文献
5.
目前,发光材料在信息、显示、照明、国防等领域得到了极其广泛的应用.随着人们对发光和发光材料基本科学问题的认识及其广阔而不可替代的应用前景的驱动,发光和发光材料领域在过去100年间迅速发展.量子效率大于1的发光及光功能材料有望在高效发光、等离子体平板显示、高效光纤激光器、高效太阳能光电池等领域得到广泛应用.深入研究光子材料的激发与发光、能量传递与转换、敏化发光与光放大等物理和光学基本科学问题,不但有益于揭示光子材料的一些新现象、新规律,而且将为光子材料与器件的设计与研制奠定理论和方法基础.本文概述了近红外量子剪裁的发展及其材料和相关机理的最近研究进展,主要包括稀土离子单掺体系双光子和三光子级联发射近红外量子剪裁、稀土离子对共掺体系近红外量子剪裁下转换.此外,本文还讨论了量子剪裁及其材料体系的应用、面临的挑战和未来的发展方向. 相似文献
6.
玻璃的最大声子能量决定稀土离子的上转换发光强度,但本研究发现:Yb^3 /Er^3 共掺锗碲酸盐玻璃在980nm LD抽运下,上转换荧光强度随着Bi2O3对PbO的取代和碱金属离子半径的增大而明显增强.而Raman光谱显示基质玻璃的最大声子能量并不随Bi2O3对PbO的取代和碱金属离子半径的增大而变化,但玻璃的最大声子密度随着Bi2O3对PbO取代和碱金属离子半径的增大而降低.从玻璃无辐射跃迁概率的角度,通过分析表明,最大声子密度的降低是玻璃上转换发光强度增强的主要原因. 相似文献
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8.
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. 相似文献
9.
A simple and efficient method for the synthesis of water-soluble NdF3 and NdF3:Ba2+ nanocrystals under hydrothermal conditions is established. The method involves the coating of the nanocrystals with a layer of hydrophilic polymer polyvinylpyrrolidone (PVP). The as-prepared products are characterized by powder X-ray diffraction, field emission scanning electronic microscopy, Fourier transform infrared spectroscopy, and photoluminescence spectroscopy. The PVP coating transforms the nanocrystals into a biocompatible material and improves the fluorescence intensity of NdF3 in the near infrared (NIR) region. The morphology of the nanoparticles changes, whereas the fluorescence intensity of NdF3 in the NIR region increases when a small amount of Ba2+ is doped into the NdF3/PVP nanoparticles. 相似文献
10.