Yb3+/Er3+/Tm3+共掺氧氟碲酸盐玻璃三基色上转换发光研究

制备了一种新的Yb3 /Er3 /Tm3 共掺氧氟碲酸盐玻璃.研究了ZnF2调整Yb3 /Er3 /Tm3 共掺氧氟碲酸盐玻璃的Raman光谱、吸收光谱和上转换荧光光谱.结果发现,该体系玻璃具有较低的声子能量,在980 nm LD激发下,可以同时观察到明显的蓝色(476nm)、绿色(530和545 nm)和红色(656nm)上转换发光.上转换蓝光(476 nm)是由于Tm3 离子1G4→3H6跃迁,上转换的绿光(530和545 nm)是由于Er3 离子2H11/2→4I15/2和4S3/2→4I15/2跃迁,上转换红光(656nm)是由于Er3 离子4F9/2→4I15/2跃迁.根据吸收光谱以及Yb3 、Er3 和Tm3 离子的能级,分析了Yb3 /Er3 /Tm3 共掺氧氟碲酸盐玻璃的上转换发光机理,发现上转换蓝光是一个三光子吸收过程,而上转换绿光和红光均为双光子吸收过程.研究结果表明,Yb3 /Er3 /Tm3 共掺氧氟碲酸盐玻璃是一种三维立体显示用激光玻璃的潜在基质材料.     

三维立体显示用稀土掺杂氧卤碲酸盐玻璃

制备了一种新的Er^3 ／Tm^3 /Yb^3 共掺氧卤碲酸盐玻璃。研究了基质玻璃的热稳定性能、Raman光谱和上转换发光。发现：氧卤碲酸盐玻璃具有好的热稳定性能和低的声子能量，在980nmLD激发下，可同时观察到明显的蓝色(476nm)、绿色(530nm和545nm)和红色(656nm)上转换发光。上转换蓝光(476nm)是由于Tm^3 离子1^G4→3^3H6跃迁，上转换的绿光(530nm和545nm)是由于Er^3 离子2^H11/2→4^I15／2和4^S3/2→4^I15/2跃迁，上转换红光(656nm)是由于Er^3 离子4^F9/2→4I15/2跃迁。     

Er3 掺杂钡镓锗玻璃上转换荧光淬灭机理研究

制备了30BaO-30Ga2O3-40GeO2-xEr2O3系统玻璃,测量了Er3 在钡镓锗玻璃中的吸收光谱.分别采用488 nm,800 nm和980 nm激发不同浓度Er3 掺杂的玻璃样品,测量了Er3 的4S3/2→4I15/2荧光光谱;并利用488 nm脉冲氙灯激发,测量了Er3 的4S3/2→4I15/2荧光衰减,讨论了Er3 掺杂浓度对4S3/2能级发光强度和荧光寿命的影响.结果表明:随着Er3 浓度的增加,4S3/2→4I15/2荧光强度先增大后减小,在Er3 浓度为1%时出现峰值;而4S3/2能级的荧光寿命呈递减趋势,荧光衰减曲线的非指数成分增加.能量分析表明:Er3 的4S3/2能级和4I15/2能级之间交叉驰豫过程是上转换荧光淬灭的主要通道,而交叉驰豫过程主要源于Er3 电偶极-电偶极间的相互作用.     

掺铒碲酸盐的热稳定性和Judd-Ofelt理论分析

利用熔融法制备掺铒TeO2-ZnO-Na2O-B2O3-GeO2碲酸盐玻璃。采用差热扫描分析法（DSC）和热分析（TMA）得到玻璃的玻璃转化温度（Tg）、玻璃析晶温度（Tx）、玻璃软化温度（Tf）和热膨胀系数（α）,应用Judd-Ofelt理论计算玻璃中Er3＋的振子强度Ωλ（λ=2,4,6）,跃迁几率Aed,荧光分支比β,辐射寿命τi。根据McCumber理论计算Er3＋离子4I13/2→4I15/2的受激发射截面σemis和荧光半高宽FWHM。得出此体系的玻璃具有高热稳定性和低热膨胀性,具有较高的Er3＋离子4I13/2→4I15/2能级跃迁效率和较好的增益带宽性能。     

Tm3 /HO3 共掺碲酸盐玻璃2.0μm发光性质研究

研究了Tm3 /HO3 离子共掺碲酸盐玻璃的光谱性质,应用Judd-Ofelt理论计算了玻璃的各项光谱参数,推导了速率方程.表明3H4→3F4自发辐射跃迁几率很小,这一跃迁发射为-自终止系统.Tm3 离子3F4上粒子数主要来源于3H4 3H6→2323F4的交叉弛豫过程.玻璃的荧光光谱表明,随着Ho2O3浓度的增加,Tm3 离子3F4→3H6跃迁的1.8μm发光强度降低,而HO3 离子5I7→5I8跃迁的2.0 μm发光强度迅速升高,说明Ho2O3浓度的增加,Tm3 离子和Ho3 离子间的能量转移作用逐渐加强.     

Er3+和Yb3+共掺ZnS纳米晶的合成及光学性能研究

采用巯基乙酸为稳定剂水热法合成了ZnS:Er/Yb纳米晶。利用XRD、TEM、XPS和荧光光谱对合成的纳米晶进行物相、形貌、化学价态及荧光性能表征。结果表明：合成的纳米晶粒度约5nm,为闪锌矿结构;荧光光谱可知,激发波长为270nm时,发射光谱中主要出现了470 nm, 530 nm和 580 nm三个发射峰,且当合成温度为120℃时,发光峰强度最大。980nm激发纳米晶时,得到了Er离子在540 nm和 650 nm处4F3/2→4I15/2 和4F9/2→4I15/2的跃迁发射峰。     

Gd2O3：Yb，Er纳米材料的制备及上转换发光研究

利用Triton X-100／正己醇／环己烷／正己烷／水制成W／O微乳反胶团体系制备Gd2O3：Yb，Er上转换材料。利用扫描电镜观察氧化物粉体的颗粒形貌均为球形；通过改变掺杂元素Yb和Er的比例，在980nm的红外光激发下，观察研究氧化物颗粒的发光性质。该粉体在波长为980nm的半导体激光器激发下发射出绿色和红色的上转换荧光，分别对应于Er^3＋离子的。^S3／2／^2H11／2→^4I15／2跃迁和。^F9／2→^I15／2跃迁。     

Er3+掺杂位置对Er3+:BaTiO3薄膜上转换发光的影响

采用溶胶-凝胶法在LaNiO3/Si衬底上制备Er3+掺杂BaTiO3薄膜.通过XRD、AFM和PL图谱分别研究薄膜的晶体结构、形貌以及上转换发光性能.结果表明,薄膜的微观结构和发光性能与Er3+掺杂晶格的位置有关.A位掺杂薄膜较B位掺杂薄膜具有较小的晶格常数和较好的结晶.PL光谱表明:A位掺杂的薄膜和B位掺杂的薄膜都于528 nm和548nm处获得较强的绿色上转换发光以及在673 nm处获得较弱的红光,分别对应Er3+离子的2H11/2→4I15/2,4S3/2→4I15/2和4F9/2→4I15/2能级跃迁.相对于B位掺杂的薄膜,A位掺杂样品有较强的绿光发射积分强度以及较弱的红光发射相对强度.这种差异可以通过薄膜的结晶状况和交叉弛豫机制来进行解释.     

Er~(3+)掺杂位置对Er~(3+):BaTiO_3薄膜上转换发光的影响(英文)

采用溶胶-凝胶法在LaNiO3/Si衬底上制备Er3+掺杂BaTiO3薄膜。通过XRD、AFM和PL图谱分别研究薄膜的晶体结构、形貌以及上转换发光性能。结果表明,薄膜的微观结构和发光性能与Er3+掺杂晶格的位置有关。A位掺杂薄膜较B位掺杂薄膜具有较小的晶格常数和较好的结晶。PL光谱表明:A位掺杂的薄膜和B位掺杂的薄膜都于528nm和548nm处获得较强的绿色上转换发光以及在673nm处获得较弱的红光,分别对应Er3+离子的2H11/2→4I15/2,4S3/2→4I15/2和4F9/2→4I15/2能级跃迁。相对于B位掺杂的薄膜,A位掺杂样品有较强的绿光发射积分强度以及较弱的红光发射相对强度。这种差异可以通过薄膜的结晶状况和交叉弛豫机制来进行解释。     

Upconversion luminescence properties of Er<Superscript>3+</Superscript> doped GeS<Subscript>2</Subscript>-Ga<Subscript>2</Subscript>S<Subscript>3</Subscript>-KCl chalcohalide glasses

Er3+ ions doped chalcohalide glasses with the composition of 56GeS2-24Ga2S3-20KCl were fabricated by a melt-quenching method.Under 800 nm laser excitation,strong green emissions centered at 525 nm and 550 nm and weak red emission centered at 660 nm were observed,which were assigned to 2H11/2→4I15/2,4S3/2→4I15/2,and 4F9/2→4I15/2 transitions,respectively.The intensity reached maximum when the Er3+ ions concentration was 0.1 mol%.The possible upconversion luminescence mechanism was proposed from the discussion...     

Comparison study of two aldehyde group finishing agents in surface modification of up-conversion luminescence materials

Surface modification of up-conversion luminescence materials (Na[Y0.57Yb0.39Er0.04]F4 modified by amino groups) by grafting and modifying with aldehyde groups was studied by means of Fourier transform infrared spectroscopy (FFIR),scanning electron microscopy (SEM),thermogravimetric analysis (TGA),and emission spectrum (EM).The surface modification effect was compared using two different finishing agents,p-phthalaldehyde and glutaraldehyde.It was found that the surface of up-conversion luminescence materials could be modified by aldehyde groups of the two finishing agents,the systematic dispersibility and the thermostability of the up-conversion luminescence material modified by p-phthalaldehyde were better than those of the material modified by glutaraldehyde,and the luminous intensity of the material modified by p-phthalaldehyde was increased.The AI (the ratio of the suspended segmental quality in the specimen to the total mass of the specimen) of the material modified by p-phthalaldehyde was higher than that of the material modified by glutaraldehyde.It is obviously seen that the embellishment effect of p-phthalaldehyde as a finishing agent was better than that of glutaraldehyde.In addition,the reasons why p-phthalaldehyde is a good finishing agent are also explained.     

溶胶凝胶法合成Dy~(3+)离子掺杂的二氧化锆及其发光特性(英文)

采用溶胶凝胶法合成 Dy3+离子掺杂的单斜与正交的二氧化锆晶体,研究了结晶温度、时间、Dy3+离子浓度对氧化锆结构的影响。比较研究了 Dy3+离子在不同结构二氧化锆中的光谱特性,从结果看出,Dy3+离子可作为荧光探针反映二氧化锆的晶体结构。     

氧化铝原料对合成SrAl2O4(Eu,Dy)材料余辉发光性能的影响

通研究不同氧化铝原材料的组成和形貌,分析它们对合成稀土铝酸盐长余辉发光材料性能的影响,发现原晶结构和晶粒类型是影响合成产物长余辉发光性能的重要因素;而通常氧化铝原料的纯度基本上可以满足合成原料的纯度要求。     

Sensitized high-order ultraviolet upconversion emissions of Gd by Er in NaYF4 microcrystals

High-order ultraviolet (UV) upconversion (UC) emissions of Gd³⁺ and Er³⁺ ions were observed in NaYF₄:Yb³⁺/Gd³⁺/Er³⁺ microcrystals under 980 nm excitation. These UC emissions came from six- and five-photon UC processes at low pump power range, which were confirmed by the pumping power dependences of UC fluorescence intensities. In these high-order UC processes, energy transfer (ET) processes of Er³⁺ → Gd³⁺ played crucial roles in populating the excited states of Gd³⁺ ions. Experiments on concentration variation and dynamic analysis revealed the ET processes between Er³⁺ and Gd³⁺ in detail. Some of possible population routes for populating excited Gd³⁺ ions were proposed based on spectral and dynamic analysis.     

溶胶-凝胶合成Er3 和Ho3 离子掺杂的Gd2(MoO4)3上转换发光纳米晶

采用柠檬酸与乙二醇溶胶-凝胶法合成了Er3 和Ho3 离子分别掺杂的铝酸钆Gd2(MoO4)3纳米晶.用XRD证实了产物的结构,用扫描电镜与透射电镜研究了产物微观形貌与尺寸.在980nm激光泵浦下,Ho3 掺杂Gd2(MoO4)3纳米晶发出很强的位于660nm的红光,而Er3 掺杂Gd2(MoO4)3纳米晶发出很强的位于540nm左右的红光.共掺Yb3 分别对Ho3 与Er3 起着显著的敏化作用.从发光强度与激光功率变化图中可知,Ho3 与Er3 的发光均属于双子光发光过程.     

White luminescence of Ho3+/Tm3+/Yb3+-codoped CaWO4 synthesized via citrate complex route assisted by microwave irradiation

The nanocrystalline Ho³⁺/Tm³⁺/Yb³⁺ co-doped CaWO₄ upconversion (UC) phosphors were successfully synthesized by a modified citrate complex method using microwave irradiation. The citrate complex precursors were heat-treated at temperature ranging from 300 to 700 °C for 3 h. Crystallization of the Ho³⁺/Tm³⁺/Yb³⁺ co-doped CaWO₄ was detected at 400 °C, and entirely completed at 600 °C. The Ho³⁺/Tm³⁺/Yb³⁺ co-doped CaWO₄ heat-treated at 600 °C showed primarily spherical and homogeneous morphology. Under the laser excitation of 980 nm, Ho³⁺/Tm³⁺/Yb³⁺ co-doped CaWO₄ shows the bright white upconversion (UC) emission visible to the naked eye, which is composed of a blue emission at 475 nm from Tm³⁺, and green and red emissions at 543 and 651 nm respectively from Ho³⁺. The coordinates of Ho³⁺/Tm³⁺/Yb³⁺ co-doped CaWO₄ in the Commission International De'eclairage (CIE) chromaticity diagram could be controlled from a cool to a warm white color depending on the Tm³⁺ and Ho³⁺ concentrations. The UC luminescent properties on Tm³⁺ and Ho³⁺ concentrations and related mechanism based on laser pump power were discussed in detail.     

ZnO纳米晶的合成、掺杂及发光性能研究

以Zn(NO_3)_2、(NH_4)_2CO_3与Y(NO_3)_3为初始原料,采用水热法制备了棒状和枝状ZnO及掺杂Y的ZnO纳米晶.采用XRD、Raman、FESEM 、EDAX和PL方法对合成产物形貌与发光性能进行表征.XRD与Raman的研究结果表明,合成的棒状和枝状ZnO纳米晶为六方纤锌矿单晶;XRD与FESEM的测试结果表明,pH值对水热产物的晶相及形貌有重要的影响;XRD结合EDAX的分析结果表明,热处理后的水热产物中Y元素掺入了ZnO基体;ZnO及ZnO-Y_2O_3的纳米晶PL谱的结果表明,产物的发光性能与制备方式有关,与此同时,ZnO-Y_2O_3纳米晶的本征发光峰发生红移,其结果与Y元素与ZnO之间的能量传递有关.     

等离子喷涂SrAl_2O_4涂层的发光性能

把发光材料稀土铕、镝掺入铝酸锶为喷涂材料,用等离子喷涂法, 将材料喷涂在钢板上.利用X射线衍射、扫描电子显微镜等分析手段对铝酸锶涂层的微观结构进行研究.通过发光光谱对铕、镝掺杂的铝酸锶涂层的发光性能进行表征,并对涂层的发光机制做初步探讨.     

Investigation on the enhancement and the suppression of persistent luminescence of Re doped Sr2EuMgSi2O7 (Re = Dy, Yb)

The enhancement and the suppression of persistent luminescence on Sr₂EuMgSi₂O₇ are investigated by Dy³⁺ or Yb³⁺ doping. The TL curves show the deep traps induced by Yb³⁺ besides the intrinsic traps. The TL intensity of deep traps is stable whereas it decreases with preheating, indicating a charge carriers transfer process from the intrinsic traps to the deep ones. The mean lifetime of charge carriers in the deep traps is longer because of greater activation energy, restraining the detrapping. The similar process dominates the Dy³⁺ doped sample with an optimum trap depth, resulting in the enhancement of persistence luminescence.     

Broadband near-infrared luminescence and tunable optical amplification around 1.55 μm and 1.33 μm of PbS quantum dots in glasses

Silicate glasses containing PbS quantum dots (QDs) with narrow size distribution were prepared through heat treatment. Transmission electron microscopy (TEM) results show that spherical PbS QDs are densely dispersed in the glassy matrix. Using ZnS-PbO to replace PbS as precursor of PbS QDs, the size distribution of PbS QDs in glasses becomes more uniform. Tunable infrared luminescence from 1100 to 2200 nm has been obtained by controlling the glassy matrix and preparation parameters. Obvious optical amplification at communication windows of 1.55 μm and 1.33 μm is probed, and the PbS QDs doped glasses using ZnS-PbO as precursor exhibit larger optical amplification. The PbS QDs doped glasses with intense optical amplification are considered to be promising candidate as gain medium for broadband fiber amplifier and tunable fiber laser.