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1.
Tm3+/Yb3+-codoped germanate-niobic (GN) and germanium-bismuth (GB) glasses have been synthesized by conventional melting and quenching method. Intense blue and weak red emissions centered at 477 and 650 nm, corresponding to the transitions 1G4→3H6 and 1G4→3H4, respectively, were observed at room temperature. The possible up-conversion mechanisms are discussed and estimated. GN glass showed a weaker up-conversion emission than GB glass, which is inconsistent with the prediction from the difference of maximum phonon energy between GN and GB glasses. In this paper, Raman spectroscopy was employed to investigate the origin of the difference in up-conversion luminescence in the two glasses. Compared with phonon side-band spectroscopy, Raman spectroscopy extracts more information including both phonon energy and phonon density. For the first time, our results reveal that, besides the maximum phonon energy, the phonon density of host glasses is also an important factor in determining the up-conversion efficiency. 相似文献
2.
Thermal stability, Raman spectra and blue upconversion luminescence properties of Tm3+/Yb3+-codoped halide modified tellurite glasses have been studied. The results showed that the mixed halide modified tellurite glass (TFCB) has the best thermal stability, the lowest phonon energies and the strongest upconversion emissions. The effect of halide on upconversion intensity is observed and discussed and possible upconversion mechanisms are evaluated. The intense blue upconversion luminescence of Tm3+ in TFCB glass may be a potentially useful material for developing upconversion optical devices. 相似文献
3.
H. Sun L. Zhang L. Wen M. Liao J. Zhang L. Hu S. Dai Z. Jiang 《Applied physics. B, Lasers and optics》2005,80(7):881-888
Yb3+/Er3+-codoped oxychloride germanate glasses have been synthesized by a conventional melting and quenching method. Structural properties were obtained based on Raman-spectra investigation, indicating that PbCl2 plays an important role in the formation of the glass network and has an important influence on the phonon density and the maximum phonon energy. The Judd–Ofelt intensity parameters and quantum efficiencies were calculated based on the Judd–Ofelt theory and lifetime measurements. The enhanced upconversion luminescence intensity of Er3+ with increasing PbCl2 content could not be explained only by the maximum phonon-energy change of the host glasses. For the first time, the effect of PbCl2 addition on phonon density, OH– content, and upconversion luminescence in oxychloride glasses has been discussed and evaluated. The results show that the effect of phonon density and OH– content on upconversion luminescence in oxychloride glasses is much stronger than that of the decrease of the maximum phonon energy. The possible upconversion luminescence mechanisms have also been estimated and are discussed. 相似文献
4.
研究了卤化铅调整Tm3+/Yb3+共掺碲酸盐玻璃的热稳定性能、Raman 光谱和上转 换发光光谱,分析了Tm3+/Yb3+共掺氧卤碲酸盐玻璃的上转换发光 机理.结果发 现:混合卤化铅调整Tm3+/Yb3+共掺碲酸盐玻璃具有好的热稳定性 能、低的声 子能量、强的上转换蓝光.这表明混合卤化铅调整Tm3+/Yb3+共掺碲 酸盐玻璃是一种上转换蓝光激光器的潜在基质材料.
关键词:
氧卤碲酸盐玻璃
上转换光谱
发光机理
上转换蓝光激光器 相似文献
5.
Hongtao Sun Junjie Yang Junjie Zhang Zhonghong Jiang 《Solid State Communications》2005,133(12):753-757
Er3+-doped oxychloride germanate glasses have been synthesized by conventional melting and quenching method. Structural and thermal stability properties were obtained based on the Raman spectra and differential thermal analysis, indicating that PbCl2 plays an important role in the formation of glass network and has an important influence on the maximum phonon energy and thermal stability of host glasses. Intense green and red emissions centered at 525, 546, and 657 nm, corresponding to the transitions 2H11/2→4I15/2, 4S3/2→4I15/2, and 4F9/2→4I15/2, respectively, were observed at room temperature. With increasing PbCl2 content, the intensity of green (525 and 546 nm) emissions increases significantly, while the red (657 nm) emission increases slowly. The results indicate that PbCl2 has more influence on the green emissions than the red emission in oxychloride germanate glasses. The possible upconversion luminescence mechanisms has also been estimated and discussed. 相似文献
6.
Meisong Liao Zhongchao Duan Lili Hu Yongzheng Fang Lei Wen 《Journal of luminescence》2007,126(1):139-144
Er3+/Yb3+ codoped fluorophosphate glasses were prepared and their thermal stabilities, Raman spectra, absorption spectra, and fluorescence spectra were measured. It is found that proper content of NaF or PbF2 is helpful for the increase of stability against crystallization. The variation of Al(PO3)3 or NaF content in the composition affects not the maximum phonon energy but the phonon density. The introduction of PbF2 decreases the phonon energy slightly. Intense green and red upconversion luminescence was observed for the fluorophosphate glass with low phosphate content. A glass matrix for upconversion luminescence requiring neither expensive raw material nor special atmospheric conditioned preparation is provided. Infrared luminescence around 1530 nm was researched. Fluorophosphate glasses with bandwidth properties and stimulated-emission cross sections better than tellurite, germanate and silicate glasses are obtained. Through the introduction of NaF, the bandwidth properties are decreased. Through the introduction of PbF2 the gain properties are increased. On the whole, it is difficult to obtain a material with the best gain properties and bandwidth properties simultaneously. There should be a compromise between them according to the demand. 相似文献
7.
Effect of Yb2O3 content on upconversion luminescence and mechanisms in Yb3+-sensitized Tm3+-doped oxyhalide tellurite glasses were investigated under 980 nm excitation. Intense blue and relatively weak red upconversion emission centered at 476 and 649 nm corresponding to the transitions 1G4→3H6 and 1G4→3H4 of Tm3+, respectively, are simultaneously observed at room temperature. The results show that upconversion blue and red emission intensities of Tm3+ first increase, reach its maximum at Yb2O3%=3 mol%, and then decrease with increasing Yb2O3 content. The effect of Yb2O3 content on upconversion intensity is discussed, and possible effect mechanisms are evaluated. The investigated results were conducing to increase upconversion luminescence efficiency of Tm3+. 相似文献
8.
研究了Tm3+/Yb3+共掺氧卤碲酸盐玻璃的上转换发光光谱,分析了Tm2O3含量对Tm3+/Yb3+共掺氧卤碲酸盐玻璃上转换发光的影响机理.结果表明:在Tm3+/Yb3+共掺氧卤碲酸盐玻璃的上转换发光中,Tm3+存在较强的浓度猝灭效应.随Tm2O3含量增加,Tm3+的上转换蓝光和红光强度先增加,后降低,在0.1mol% Tm2O3达到最大.该结果有助于进一步提高Tm3+的上转换发光效率. 相似文献
9.
Hongtao Sun Chunlei Yu Liyan Zhang Dongbin He Lili Hu 《Solid State Communications》2005,134(9):595-599
Structural and up-conversion fluorescence properties in ytterbium-sensitized thulium-doped novel oxychloride bismuth-germanium glass have been studied. The structure of novel bismuth-germanium glass was investigated by peak-deconvolution of Raman spectrum, and the structural information was obtained from the peak wave numbers. The Raman spectrum investigation indicates that PbCl2 plays an important role in the formation of glass network, and has an important influence on the up-conversion luminescence. Intense blue and weak red emissions centered at 477 and 650 nm, corresponding to the transitions 1G4→3H6 and 1G4→3H4, respectively, were observed at room temperature. The possible up-conversion mechanisms are discussed and estimated. This novel oxychloride bismuth-germanium glass with low maximum phonon energy (∼730 cm−1) can be used as potential host material for up-conversion lasers. 相似文献
10.
High near-infrared transparency Tm3+-doped germanate bulk glass and fiber have been fabricated and 2 μm emission properties demonstrated. Energy-transfer processes
in the germanate glass and fiber are discussed. The emission spectra are obtained from both bulk glass and fiber with the
excitation of a 794 nm laser diode. The results indicate that the line width of the Tm3+:3F4→3H6 emission spectra measured in fibers is narrower than that of the bulk glass sample and shifts to longer wavelengths with
increment of fiber length. The extended overlap integral method is used to calculate the microparameters of energy transfer
and critical distance. A model is derived to better understand of the energy-transfer process of thulium ions in the germanate
glasses responsible for emission at 2 μm. The study indicates that Tm3+-doped germanate fibers with a large core diameter has proved to be promising infrared optical and high-power level laser
materials. 相似文献
11.
In this paper, we report the near-infrared luminescence from the Er3+/Yb3+, Tm3+/Yb3+, Er3+/Tm3+ and Nd3+ ions-doped TeO2-ZnO-B2O3-Li2O-Na2O glasses for optical amplification. The X-ray diffraction (XRD) and differential scanning calorimetry (DSC) profiles of the host glass matrix have been carried out. From the DSC thermogram, glass transition (Tg), crystallization (Tc) and melting (Tm) temperatures have been evaluated. The near-infrared spectra of Er3+/Yb3+, Tm3+/Yb3+, Er3+/Tm3+ and Nd3+ ions-doped glasses have shown full-width at half-maxima (FWHM) around 58, 127, 87 and 35 nm, respectively. These glasses with better thermal stability and broad near-infrared emissions should have potential applications in broadly tunable laser sources and broadband optical amplification at low-loss telecommunication windows. 相似文献
12.
Xiaoluan Liang 《Journal of luminescence》2010,130(3):429-433
Phosphate glasses and glass ceramics doped with Er3+ and co-doped with Er3+-Tm3+ are presented in this work. The luminescence properties have been characterized by absorption, excitation and emission spectra. All samples excited by blue light could emit a combination of blue/green/orange/red wavelength giving white light. For Er3+-doped glasses, a self-quenching effect has been obtained and an adjustable tune comes out after crystallization. For co-doped glasses, the red emission at 651 nm has been enhanced due to the existence of Tm3+, which could be relative to both the overlapped emissions and the energy transfer from Tm3+ to Er3+. 相似文献
13.
Low phonon energy Tm3+/Ho3+/Yb3+ triply doped bismuth tellurite glasses exhibiting multicolor upconversion fluorescences have been fabricated and characterized. The multicolor fluorescence composed of three primary colors green, red and blue upconversion emissions from Ho3+ and Tm3+ has been investigated. By adjusting the excitation power, the fluorescence colors can be tuned from multicolor to white color, and the dependence of color tunability on pump power has been presented in the CIE 1931 chromaticity diagram. With the increase in pumping power, the color coordinates move along the down-left direction and hit the equal energy point. The upconversion and color tunability via changing the pump power of infrared excitation in Tm3+/Ho3+/Yb3+ triply doped bismuth tellurite glasses will lead to new breakthrough in the field of three-dimensional solid-state displays and white-light emitting devices. 相似文献
14.
研究了混合形成体效应对掺铒碲酸盐玻璃热力学稳定性、1.53 μm发光特性和上转换发光强度的影响.通过拉曼光谱测试,分析了WO3,Nb2O5,GeO2等氧化物对Er3+离子配位场结构,以及对发光谱的非均匀展宽机理的作用.结果表明,通过掺杂适当声子能量的网络形成体氧化物,不但可获得热力学稳定性较好的玻璃,还可有效降低Er3+离子4I11/2能级的寿命,在抑制Er3+离子在可见光波段的上转换发光的同时不致劣化其在1.53 μm的发光特性.本文制得的碲酸盐玻璃具有较大的受激发射截面((9.64—10.96)×10-21cm2)和荧光半高宽(FWHM)(50—67 nm),热力学稳定性良好,是一种理想的掺Er3+宽带有源光纤用基质玻璃.
关键词:
掺铒碲酸盐玻璃
混合形成体
1.53 μm发光
声子能量 相似文献
15.
T. N. Vasilevskaya A. A. Kaplyanskii A. B. Kulinkin S. P. Feofilov 《Physics of the Solid State》2003,45(5):961-968
The properties of Cr3+-doped Li2Ge7O15 (LGO) lithium germanate nanocrystals produced in lithium germanate glasses under isothermal heating were studied. The samples were characterized by x-ray diffraction and small-angle scattering, as well as by transmission electron microscopy. The luminescence spectra of the impurity chromium measured in lithium germanate glasses containing LGO crystals revealed transitions in Cr3+ ions residing in the glass phase and in LGO crystallites starting from extremely small clusters. This provided the possibility of following the process of crystallization of the lithium germanate glass from Cr3+ luminescence spectra. The effects observed in the Cr3+ luminescence spectrum revealed a ferroelectric phase transition in LGO nanocrystals embedded in the glass. 相似文献
16.
制备了70TeO2-20WO2-10ZnO-xTm2O3系统玻璃,根据所测玻璃的吸收光谱,应用Judd-Ofelt(J-O)理论计算出Tm3+离子在碲酸盐玻璃的J-O强度参数、Tm3+在玻璃中的自发辐射概率A、荧光分支比β及荧光辐射寿命 τR 等各项光谱参数.测定了玻璃的荧光光谱,并计算了Tm3+在碲酸盐玻璃中的荧光有效线宽、峰值受激发射截 面.比较了Tm3+在不同掺杂浓度下的光谱特性,认为当Tm2O3掺杂浓度达到 0.8wt%—1wt%时,所获得的荧光强度与荧光线宽达到最佳值,掺Tm3+ 碲酸盐玻璃是一种理想的S波段宽带光纤放大器用基质材料.
关键词:
碲酸盐玻璃
宽带光纤放大器
荧光线宽
荧光峰值发射截面 相似文献
17.
采用高温熔融法制备了组分为TeO2-ZnO-Na2O的Tm3+离子单掺和Tm3+/Yb3+共掺碲酸盐玻璃,应用Judd-Ofelt理论计算分析了玻璃样品的强度参量Ωt(t=2, 4, 6),自发辐射跃迁几率A,荧光分支比β和荧光辐射寿命τrad等光谱参量,测量得到了不同Yb3+离子掺杂浓度下玻璃样品的Tm3+离子上转换发光谱.结果显示,在980 nm泵浦光激励下玻璃样品发射出强烈的近红外上转换荧光.对Tm3+离子上转换发光分析表明,强烈的Tm3+离子近红外上转换发光主要来自于Yb3+/Yb3+离子间的共振能量传递以及基于单声子和双声子辅助的Yb3+/Tm3+离子间的非共振能量传递过程,并进一步计算得到了声子贡献比和能量传递系数.最后,计算分析了Tm3+:3F4→3H6能级间跃迁的1.8 μm波段吸收截面、受激发射截面和增益系数.研究表明,Yb3+/Tm3+共掺TeO2-ZnO-Na2O玻璃可以作为近红外波段固体激光器的潜在增益基质. 相似文献
18.
The thermal characterization and spectroscopic properties of Er3+-doped 0.6GeO2-(0.4-x)PbO-xPbF2 glasses were investigated experimentally. With the replacement of PbO by PbF2 the thermal stability of glasses is improved and the infrared fluorescence intensity at 1530 nm is increased. The Judd-Ofelt intensity parameters, radiative transition rates, and fluorescence lifetimes of the excited 4I13/2 level of Er3+ ions were calculated from Judd-Ofelt theory. The asymmetric ligand field around Er3+ ions resulted from the incorporation of PbF2 into germanate glasses, broadens the infrared emission spectra at 1530 nm. Upconversion luminescence in the investigated glasses was observed at room temperature under the excitation of 976 nm laser diode. The glass 0.6GeO2-0.3PbO-0.1PbF2 exhibits the maximum upconversion emission intensity, while no frequency upconversion luminescence was observed in the 0.6GeO2-0.4PbO glass. The quadratic dependence of the green and red emissions on excitation power indicates that two-photon absorption contributes to the visible emission under the 976-nm excitation. 相似文献
19.
We report on 2.0-μm emission characteristic and energy transfer of Ho3+-doped tellurite glass sensitized by Tm3+ upon excitation of a conventional 808 nm laser diode. The Judd-Ofelt strength parameters, spontaneous radiative transition
probabilities and radiative lifetime of Ho3+ have been calculated from the absorption spectra by using the Judd-Ofelt theory. Significant enhancement of 2.0-μm emission
of Ho3+ has been observed with increasing Tm3+ doping up to 0.7 mol%. The energy transfer coefficient of the forward Tm3+→Ho3+ is approximately 17 times larger than that of the backward Tm3+←Ho3+ energy transfer. Our result indicates that the maximum gain of 2.0-μm emission, assigned to the transition of 5I7→5I8 of Ho3+, might be achieved from the tellurite glass at the concentration of 0.5 mol% of Tm2O3 and 0.15 mol% of Ho2O3. The high gain coefficient and quantum efficiency (1.16) along with the large value of the product of the stimulated emission
cross-section and the measured radiative lifetime (4.12×10−27 m2s) of the Ho3+/Tm3+-codoped tellurite glasses might find potential applications in efficient 2.0-μm laser. 相似文献
20.
研究了Er3+/Yb3+共掺、Tm3+/Yb3+共掺、Er3+/Yb3+/Tm3+共掺碲酸盐玻璃在970nm抽运下的荧光光谱和上转换光谱性质,测试了Er3+离子的4I11/2和4I13/2能级荧光寿命变化情况.结果发现Er3+/Yb3+/Tm3+共掺碲酸盐玻璃的常规荧光谱线在1450—1700nm区域明显加宽,并在1630nm有一荧光峰,可能是Tm3+:1G4→3F2跃迁产生.上转换发光研究表明,由于碲酸盐玻璃声子能量低的缘故,三种共掺系统下都存在上转换发光现象.在Er3+/Yb3+/Tm3+共掺中,上转
关键词:
Er3+/Yb3+/ Tm3+共掺
碲酸盐玻璃
荧光
上转换光谱 相似文献