TmYb共掺氟氧化物玻璃的间接上转换敏化发光的研究

研究了Tm(0.1)Yb(10.9)氟氧化物玻璃在800nm半导体激光激发下的间接上转换敏化发光现象.通过Tm(0.1)Yb(3)：ZBLAN玻璃和Tm(0.1)Yb(10.9)氟氧化物玻璃中Tm³⁺离子上转换发光的比较研究,发现在间接上转换敏化的情况下,Tm(0.1)Yb(10.9)氟氧化物玻璃中Tm³⁺离子的上转换发光极大地增强,超过了Tm(0.1)Yb(3)：ZBLAN玻璃的水平.说明在此类上转换激发机制下,有着较高的稀土溶解度和较大的截止声子能量的材料可能有最佳的上转换效率,它将可能有比目前最好的ZBLAN材料高许多的上转换发光强度,这对于上转换研究迅速走向实际应用有重大的意义.目前尚未见到其他类似研究报道. 关键词：     

Experimental study on a nonlinear photonics process of Er(0.5)Yb(3):FOV oxyfluoride nanophase vitroceramics

We study the nonlinear photonics of rare-earth-doped oxyfluoride nanophase vitroceramics (FOV), oxyfluoride glass (FOG), and ZBLAN fluoride glass. We found that an interesting fluorescence intensity inversion phenomenon between red and green fluorescence occurs from Er(0.5)Yb(3):FOV. The dynamic range summation operator of the intensity inversion between red and green fluorescence of Er(0.5)Yb(3):FOV is about 5.753 x 10(2), which is 100 to 1000 times larger than those of other materials. One of the applications of this phenomenon is double-wavelength fluorescence falsification-preventing technology, which is proved to possess the novel antifriction loss and antiscribble properties.     

Tm(0.1)Yb(10.9)氟氧化物玻璃陶瓷的直接上转换敏化发光

本文首次研究了掺杂Ｔｍ（０．１）Ｙｂ（１０．９）氟氧化物玻璃陶次居９６６ｎｍ半导体激光激发下的直接上转换敏化发光现象。测量艰现存在很强的＾１Ｇ４→＾３Ｈ６的４７７ｎｍ的三光子和＾３Ｆ４→＾３Ｈ６的７９９．５ｎｍ双光子上转换荧光以及较弱的＾１Ｄ２→＾３Ｈ６的３６１ｎｍ,＾１Ｄ２→＾３Ｈ４的４４９．５ｎｍ,＾１Ｇ４→＾３Ｆ４的６４７．０ｎｍ和＾３Ｆ３→＾３Ｈ６的多个上转换发光。     

Tm(0.1)Yb(10.9)氟氧化物玻璃的直接上转换敏化发光

本文首次研究了Tm(0.1)Yb(10.9)氟氧化物玻璃在966nm半导体激光激发下的直接上转换敏化发光现象。测量发现存在很强的^1G4→^3H6的474nm三光子和较弱的^1D2→^3H6的362nm,^1D2→^3F4的452nm,^1G4→^3F4的650nm三光子以及^3F3→^3H6的681nm二光子上转换发光。并对他们的上转换机理做了简要的讨论分析。     

掺Er3+氟氧化物玻璃陶瓷的直接上转换敏化发光

研究了ErYb共掺的氟氧化物玻璃陶瓷的直接上转换敏化发光现象,发现其上转换机理主要是 Er³⁺与Yb³⁺离子间的能量传递上转换而不是Er³⁺离子 的步进多光子吸收.研究发现由于稀土离子优先富集到Pb_xCd_1-xF2微晶中,形成数个稀土离子组成的耦合团,使其存在强烈的团簇效应,一方面导 致了上转换荧光非常强,另一方面也导致了上转换荧光随抽运激光功率的对数变化F-P曲线 存在逐 关键词： 直接上转换敏化 氟氧化物玻璃陶瓷 上转换合作辐射荧光     

氟氧化物氟化物五磷酸盐玻璃中Er3+的直接上转换增敏发光的比较

本文研究了ErYb共掺的氟氧化物玻璃 (ErYb:FOG)、氟化物ZBLAN玻璃和五磷酸盐非晶在 966nm半导体激光激发下的直接上转换敏化发光现象。发现有丰富的上转换发光现象 ,这是由于样品中Yb3 的浓度很高 ,Er3 Yb3 ,Yb3 Yb3 离子之间的相互作用和能量传递作用都很强造成的。研究发现ErYb :FOG玻璃的直接上转换增敏发光比磷酸盐大 1 0 0～ 1 0 0 0 0 0倍 ;而很有趣的结果在于氟氧化物玻璃的直接上转换增敏发光与ZBLAN玻璃接近 ;这对于提高频率上转换的综合性能是很有意义的。     

Strong cooperative upconversion luminescence of ytterbium doped oxyfluoride nanophase vitroceramics

The strong 479.1 nm blue cooperative upconversion luminescence of ytterbium Yb³⁺ ion doped oxyfluoride nanophase vitroceramics (Yb:FOV) is studied in this article. It is found that the 479.1 nm blue cooperative upconversion luminescence strength of Yb(5):FOV is 230 times greater than that of fluoride glass Yb(3):ZBLAN. The large enhancement on cooperative upconversion blue luminescence of this article results from the comprehensive improvement on the aspects of better coupled chance of the Yb³⁺-Yb³⁺ cluster, less cross-relaxation, better concentration contribution of Yb³⁺ activator, non-saturation, and better upconversion luminescence efficiency.     

Comprehensive research about the cooperative up-conversion luminescence of the ytterbium-doped oxyfluoride vitroceramics

The cooperative up-conversion blue luminescence of Yb^{3+} ion-doped oxyfluoride vitroceramic material (Yb:FOV) and the influence of co-doped Ho^{3+} ion, when excited by a 960 nm diode-laser, are studied in this paper. A strong blue 479.1 nm up-conversion luminescence of the Yb:FOV material is discovered. It is found that the 479.1 nm luminescence results from the cooperative up-conversion of the coupled states of the Yb^{3+}－Yb^{3+} clusters formed by two adjacent Yb^{3+} ions. The measured cooperative up-conversion luminescence main peak 479.1 nm of this paper is different from the characteristic fluorescence main peak of the Tb^{3+} ion positioned at about 495－504 nm wave-range. Our result coincides with all the published correct papers, whose cooperative up-conversion luminescence main peaks of the direct Yb^{3+}－Yb^{3+} clusters are all positioned at about 476－480 nm wave-range. All of these indicate that the large cooperative up-conversion blue luminescence of the direct Yb^{3+}－Yb^{3+} clusters discovered in this paper is stable. It further proves that the cooperative up-conversion green luminescence may result from the Yb^{3+}-Tb^{3+} cooperative effect. In particular, the original work of this paper improves considerably on the traditional concept by the experimental facts that the blue 479.1 nm cooperative up-conversion luminescence strength of Yb(5):FOV is 230 times greater than that of fluoride glass Yb(3):ZBLAN. This is a great development to meet the practical requirements for blue up-conversion luminescence strength. This result indicates that the large cooperative up-conversion blue luminescence could be achieved excellently by using a suitable material, such as oxyfluoride vitroceramic, which provides a better chance to form better Yb^{3+}－Yb^{3+} clusters and has less relaxation to keep the more efficient up-conversion luminescence. It is also found that impurities seriously reduce the cooperative up-conversion luminescence intensity due to the cross-relaxation from the Yb^{3+}－Yb^{3+} clusters, which means that the cooperative up-conversion blue luminescence could be further improved by pure Yb^{3+} ion-doped materials that have as few impurities as possible to reduce the cross-relaxation. The large cooperative up-conversion blue luminescence of Yb(5):FOV also comes from its higher concentration (5 mol%) of activator Yb^{3+} ion which acts well because the cooperative up-conversion blue luminescence intensity varies linearly against the square of the concentration of Yb^{3+} ions in the range of 0.5－5 mol%. In summary, the great improvement of our work on cooperative up-conversion blue luminescence results from the comprehensive enhancement of the factors of better-coupled chance of the Yb^{3+}－Yb^{3+} clusters, less cross-relaxation, better concentration contribution of Yb^{3+} activator, non-saturation, and better up-conversion luminescence efficiency.     

Tm3+ ,Yb3+共掺微晶玻璃蓝色上转换荧光的温度特性

制备了Tm³⁺,Yb³⁺共掺氟氧化物微晶玻璃, 在980 nm二极管激光器泵浦下研究了其上转换发光。发现将前驱玻璃进行热处理后,源于Tm³⁺的¹G₄能级到基态³H₆跃迁所产生的蓝色上转换荧光在463 nm和476 nm出现明显劈裂。在此基础上分析了该劈裂蓝色上转换荧光在303~623 K范围内的温度特性。结果表明:Tm³⁺,Yb³⁺共掺氟氧化物微晶玻璃蓝色上转换荧光可应用于光学测温,其测温最大灵敏度为4.2×10^-4 K^-1,相应温度为352 K。     

纳米相氟氧化物玻璃陶瓷中Er3+Yb3+离子对的量子剪裁发光造成的强的光谱调制

研究了纳米相氟氧化物玻璃陶瓷中Er3+Yb3+离子对的量子剪裁发光造成的强的光谱调制现象。测量了Er3+Yb3+双掺纳米相氟氧化物玻璃陶瓷的X射线衍射谱、表面形貌、激发光谱、吸收光谱、和发光光谱;而且也与Tb3+Yb3+双掺纳米相氟氧化物玻璃陶瓷的相对应的光谱参数进行了比较。发现378 nm光激发样品(A) Er(1%)Yb(8.0%)∶FOV和样品(B) Er(0.5%)Yb(3.0%)∶FOV所导致的652.0 nm红色发光强度为522 nm光激发时的680.85倍和303.80倍;我们还发现378 nm光激发所导致的样品(A) Er(1%)Yb(8.0%)∶FOV和样品(B) Er(0.5%)Yb(3.0%)∶FOV的 652.0 nm红色发光强度为样品(C) Er(0.5%)∶FOV 的491.05和184.12倍。我们还发现在378 nm光激发时的样品(A) Er(1%)Yb(8.0%)∶FOV和样品(B) Er(0.5%)Yb(3.0%)∶FOV的{978.0和1 012.0 nm}红外发光强度依次分别为样品(C) Er(0.5%)∶FOV 的{58.00和293.62}倍和{25.11和 67.50}倍。更进一步,对于652.0 nm波长发光的激发谱,发现(A) Er(1%)Yb(8.0%)∶FOV和(B) Er(0.5%)Yb(3.0%)∶FOV的378.5 nm激发谱峰强度是(C) Er(0.5%)∶FOV的大约606.02和199.83倍。同时,也发现样品(A) Er(1%)Yb(8.0%)∶FOV和样品(B) Er(0.5%)Yb(3.0%)∶FOV的一级量子剪裁红外1 012或978 nm发光强度为样品(D) Tb(0.7%)Yb(5.0%)∶FOV的二级量子剪裁红外976 nm发光强度的101.38和29.19倍。发现的该量子剪裁是目前所报道的最强的量子剪裁。因此,相信所发现的氟氧化物纳米玻璃陶瓷中Er3+Yb3+离子对的一级量子剪裁发光是强的可以作为量子剪裁层应用到提高晶硅太阳能电池的发电效率。研究结果也能加速对目前国际热点的下一代环保的光谱调制太阳能电池的探索。     

Blue Upconversion Luminescence from Yb~(3 )-doped Oxyfluoride Vitroceramics Excited by 960nm Laser

Ｔｈｅｂｌｕｅｌｉｇｈｔｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｎｔｅｒｅｓｔｉｎｇｔｏｐｉｃｓ[1～ 8] .ＴｈｉｓｐａｐｅｒｉｎｖｅｓｔｉｇａｔｅｓｔｈｅｂｌｕｅｕｐｃｏｎｖｅｒｓｉｏｎｌｕｍｉｎｅｓｃｅｎｃｅｐｈｅｎｏｍｅｎｏｎｏｆＹｂ3 ｄｏｐｅｄｏｘｙｆｌｕｏｒｉｄｅｖｉｔｒｏｃｅｒａｍｉｃｓＹｂ( 5)∶ＦＯＶａｎｄＹｂ( 0 .5)∶ＦＯＶｗｈｅｎｅｘｃｉｔｅｄｂｙ 96 0ｎｍｄｉｏｄｅｌａｓｅｒ .Ａｎｅｗｋｉｎｄｏｆｕｐ -ｃｏｎｖｅｒｓｉｏｎｃｏｏｐｅｒａｔｉｖｅｒａｄｉａｔｉｏｎｆｌｕｏｒｅｓｃｅｎｃｅｗ…     

Spectroscopic properties and mechanism of Tm^3＋/Er^3＋/Yb^3＋ co-doped oxyfluorogermanate glass ceramics containing BaF2 nanocrystals

Transparent Tm^3＋/Er^3＋/yb^3＋ co-doped oxyfluorogermanate glass ceramics containing BaF2 nanocrystals are prepared. Under excitation of a 980-nm laser diode （LD）, compared with the glass before heat treatment, the Tm^3＋/Er^3＋/yb^3＋ co-doped oxyfluorogermanate glass ceramics can emit intense blue, green and red up-conversion luminescence and Stark- split peaks; X-ray diffraction （XRD） and transmission electron microscope （TEM） results show that BaF2 nanocrystals with an average diameter of 20 nm are precipitated from the glass matrix. Stark splitting of the up-conversion luminescence peaks in the glass ceramics indicates that Tm^3＋, Er^3＋ and （or） Yb^3＋ ions are incorporated into the BaF2 nanocrystals. The up-conversion luminescence intensities of Tm^3＋, Er^3＋ and the splitting degree of luminescence peaks in the glass ceramics increase significantly with the increase of heat treat temperature and heat treat time extension. In addition, the possible energy transfer process between rare earth ions and the up-conversion luminescence mechanism are also proposed.     

ErYb:氟氧化物玻璃陶瓷的上转换发光特征饱和现象的综合分析

研究了Er3+和Yb3+双掺的氟氧化物玻璃陶瓷在966 nm激光激发下的上转换发光的饱和现象。详细的分析发现了它存在一种能量扩展导致的“特征饱和现象”,也就是说上转换发光强度I随激光功率P而改变的双对数曲线的斜率随着激光光斑的增大而明显增大至正常的多光子关系。还发现布居耗空所导致的“典型饱和现象”也有较大的影响,它导致了logI-logP曲线会随着激光功率的增加而逐渐弯曲,而激光功率的减小会导致“典型饱和现象”也减小甚至完全消失。     

稀土离子间反斯托克斯能量传递计算的改进 2.数值模拟计算和分析

对稀土离子能级的动力学过程进行了数值计算,并对各个能级的布居概率改变进行了分析。发现如果不考虑斯托克斯过程和反斯托克斯过程之间的区别而采用原有声子辅助能量传递理论中相同的计算公式对待两种过程的话,得到的理论计算结果就与我们实验得到的校准的结果不一致,为了能够准确描述反斯托克斯能量传递过程,众所周知的量子喇曼理论相对于经典拉曼理论在斯托克斯与反斯托克斯过程的强度比上所增加的比值系数exp{ΔE/kT}被首次成功地引入来描述反斯托克斯能量传递。在能量传递计算理论中引入该比值系数之后,理论计算结果与实验结果符合的非常好,并且发现该比值系数在对纳米尺度材料的光子学研究探索中会发挥至关重要的作用。     

Er3+-Yb3+-Tm3+共掺CdF2:PbF2基玻璃中的荧光特性及其上转换机制

在 98 0nm半导体激光激发下 ,在Er3 Yb3 Tm3 共掺玻璃样品中得到了如下的 5条较强的上转换荧光带 ,分别是近红外 (80 0nm) ,红 (6 4 5nm) ,绿 (5 4 5和 5 2 5nm) ,蓝 (4 80nm)及紫 (4 0 7nm)。与Er3 Yb3 共掺样品相比 ,Tm3 的加入使得 4 80nm的蓝光显著增强 ,这应与Tm3 特殊的能级结构有关 ;荧光强度随激发功率变化的双对数曲线表明 4 80nm蓝光发射是双光子激发过程 ,为两个Yb3 的合作上转换敏化发光 ,随着激发功率的增加 ,4 80nm荧光的logI logP曲线的斜率将变小 ,逐渐向下“弯曲”。作者详细的分析了各条荧光带的上转换机制 ;并用速率方程讨论了稳态情况下 4 80nm蓝色上转换荧光强度随激发功率变化的关系 ,其结果与实验一致。     

1 520 nm激光激发的Er(0.5):FOG材料的上转换发光与立体显示研究

立体显示为现代重要的科学前沿。上转换三维立体显示为一种新颖的自体视三维立体显示,在1996年被评为十大科技创新成就之一,现正向应用快速发展。研究了1 520 nm半导体激光激发的Er(0.5):FOG材料的上转换发光,发现了(407.43, 411.20 nm), (522.51m, 528.57 nm), (540.53m, 543.70,549.00 nm), (654.75m, 665.50 nm), 和802.10m nm的上转换发光(m代表主峰),依次为(2G4F2H)_9/2→4I_15/2, 4H_11/2→4I_15/2, 4S_3/2→4I_15/2, 4F_9/2→4I_15/2和4I_9/2→4I_15/2的跃迁。值得注意的是上转换发光强度随激光功率变化的双对数曲线的斜率有各种各样的值。通过详细研究发现(407.43, 411.20 nm)的(2G4F2H)_9/2→4I_15/2上转换发光是四光子荧光;(522.51m, 528.57 nm)的2H_11/2→4I_15/2,(540.53m, 543.70,549.00 nm)的4S_3/2→4I_15/2和(654.75m, 665.50 nm)的4F_9/2→4I_15/2的上转换发光为三光子荧光;而802.10m nm的4I_9/2→4I_15/2上转换发光为双光子荧光。很明显从基态4I_15/2到第一激发态的吸收很大,因为它的振子强度f和与1 520 nm激光的匹配都很好,随后的起源于第一激发态的能量传递和相继吸收都很易于发生,这导致了1 520 nm激光激发下的Er(0.5): FOG材料的丰富和有意义的上转换发光现象。     

Blue Upconversion Luminescence from Yb3+-doped Oxyfluoride Vitroceramics Excited by 960nm Laser

This paper investigates the upconversion luminescence of Yb3+-doped oxyfluoride vitroceramics excited by 960 nm diode laser. A new upconversion cooperative radiation luminescence is found, which is rather strong and positioned at 479.5 nm. It comes from a coupled state of two Yb3+ ion cluster. It is of significance due to the effective method to obtain compact blue light.     

Hydrothermal synthesis of Yb~(3+),Tm~(3+) co-doped Gd_6MoO_(12) and its upconversion properties

Yb3+,Tm3+co-doped Gd6 Mo O12phosphors with different morphologies are prepared by the hydrothermal method.The dendrites present different morphologies(including hexagonal prisms,spindles,and spheres) after changing the p H value and edetate disodium(EDTA) usage.It is found that each of the two factors plays a crucial role in forming different morphologies.The up-conversion(UC) luminescence is studied.Under 980-nm semiconductor laser excitation,relatively strong blue emission and weak red emission are observed.Finally,the effect of pumping power on the UC luminescence properties and the level diagram mechanism of Gd6 Mo O12:Yb3+/Tm3+phosphor are also discussed.     

氟化物中Yb3+对Ho3+, Tm3+的直接敏化上转换作用

采用双掺杂(Yb^3 ／Ho^3 )和多掺杂(Ho^3 ／Yb^3 ／Tm^3 )方式,研究了氟化物中Yb^3 对Ho^3 ,Tm^3 的直接敏化上转换作用,并对它们在980nm激光激发下的上转换光谱特性进行了比较,对它们的上转换机理作了详细的讨论分析。观测到两处很强的上转换发光,分别是Yb^3 ／Ho^3 共掺杂体系中^5F4^5S2(Ho^3 )→^5Is(Ho^3 )的荧光跃迁和Ho^3 ／Yb^3 ／Tm^3 共掺杂体系中^3H4(Tm^3 )→H6(Tm^3 )的荧光跃迁。还发现由于添加了Tm^3 ,减弱了Yb^3 ／Ho^3 共掺杂体系中Ho^3 在可见光范围的上转换发光强度。     

Infrared quantum cutting conversion luminescence of Tb(0.7)Yb(3):FOV

The infrared quantum cutting of oxyfluoride nanophase vitroceramics Tb(0.7)Yb(3):FOV has been studied in the present paper. The actual quantum cutting efficiency formula calculated from integral fluorescence intensity is extended to the case of Tb(0.7)Yb(3):FOV. The visible and the infrared fluorescence spectra and their integral fluorescence intensities are measured from static fluorescence experiment. Lifetime curve is measured from dynamic fluorescence experiment. It is found that the total actual quantum cutting efficiency η of the excited ⁵D₄ level is about 93.7%, and that of excited (⁵D₃, ⁵G₆) levels is 93.5%. It is also found that the total theoretical quantum cutting efficiency upper limit η_x%Yb of the 485.5 nm excited <⁵D₄ level is about 121.7%, and that of 378.5 nm excited (⁵D₃, ⁵G₆) levels is 137.2%.