Spectra properties of Yb~(3+),Er~(3+):Sc_2SiO_5 crystal

The influence of Er3+ ions on the spectra of Yb~(3+),Er~(3+): Sc_2 SiO_5(SSO) single crystal, which was obtained by Czochralski(Cz) method, is discussed. The absorption coefficient at 980 nm was 13.36 cm~(-1) with a peak absorption cross-section of 1.46 × 10~(-20) cm2. The emission cross-sections at 1034 nm and 1062 nm were 5.5 × 10~(-21) cm~2 and4.9 × 10~(-21) cm~2, respectively. The fluorescence lifetime was estimated as 1.24 ms at 1061 nm. The mechanical properties of SSO single crystal were also presented.     

Temperature dependence of spectral and laser properties of Er~(3+)/Al~(3+) co-doped aluminosilicate fiber

Using a heavily erbium-doped aluminosilicate fiber prepared by the sol-gel method combined with high temperature sintering, the temperature dependence of the spectrum around the 1.55 nm band and single-mode fiber laser properties were investigated, respectively. The absorption cross section increases 29.2% at ～1558 nm with the temperature increasing from 20°C to 140°C, while the emission cross section slightly increases4.3%. In addition, the laser slope of the heavily erbium-doped aluminosilicate fiber at 1558 nm decreases4.4% from 10.8% to 6.4% with the temperature increasing from 18°C to 440°C. Meanwhile, an experiment lasting3 h proves that the fiber laser has excellent stability below 440°C.     

Er~(3+),Yb~(3+):glass-Co~(2+):MgAl_2O_4 diffusion bonded passively Q-switched laser

A Co~(2+):spinel passively Q-switched erbium-ytterbium-phosphate glass bonded laser pumped at 940 nm is reported.A pulse energy of 210 μJ, a peak power over 70 kW, and beam quality M~2 parameter of 1.2 are obtained under a pump power of 235 mW. An unbonded laser output experiment with the same dimension of the active material and the saturable absorber as the bonded laser output experiment is carried out. The reason why the output in the bonded laser is improved is determined.     

HO3+单掺杂及其与Yb3+、Er3+共掺杂硼硅酸盐玻璃上转换发光的光谱分析

采用高温固相烧结法制备了HO3+单掺杂、HO3+/Yb3+共掺杂、HO3+/Er3+共掺杂和Ho3+/Yb3+/Er3+共掺杂等系列硼硅酸盐玻璃,测量了样品的激发光谱和发射光谱.结果表明:Ho3+单掺杂样品的激发光谱与发射光谱的强度随其浓度增加而逐渐减弱,原因是高浓度掺杂导致Ho3+离子产生猝灭效应;Ho3+/Yb3+...     

Efficient up-conversion Yb~(3+), Er~(3+) co-doped Na_5Lu_9F_(32) single crystal for photovoltaic application under solar cell spectrum excitation

Yb~(3+)/Er~(3+)co-doped Na_5Lu_9F_(32) single crystals used as a spectral up-converter to improve the power conversion efficiency of perovskite solar cells are prepared via an improved Bridgman approach. Green and red up-conversion(UC) emissions under the excitation of near-infrared(NIR) bands of 900–1000 nm and1400–1600 nm can be observed. The effectiveness of the prepared materials as a spectral converter is verified by the enhancement of power conversion efficiency of perovskite solar cells. The sample with a UC layer is 15.5%more efficient in converting sunlight to electricity compared to the UC layer-free sample due to the absorption of sunlight in the NIR range. The results suggest the synthesized Yb~(3+)/Er~(3+)co-doped Na_5Lu_9F_(32) single crystals are suitable for enhancing the performance of perovskite solar cells.     

Er3＋ ion concentration effect on transient and steady-state behavior in Er3＋ ：YAG crystal

The effect of Er3＋ ion concentration on transient and steady-state behavior in 45-nm Er3＋ ：YAG crystal is investigated. It is shown that by changing the signal field, the coherent field and the concentration of Er3＋ ions in the crystal, the absorption, dispersion, and group index of the weak probe field can be adjusted. Also, it is found that the probe absorption occurs in the presence of population inversion and probe amplification is obtained in the absence of population inversion.     

多体系多波长计算光度法同时测定镧铈谱钕钐铕钆

本文以ＤＢＣ－偶氮氯膦为显色剂,并且在显色体系中加入不同量的ＥＤＴＡ－Ｎａ２Ｐ２Ｏ７作为竞争配位剂,使得七组分轻稀土组分间吸收光谱灵敏度的差别逐渐加大,从而增加了轻稀土混合物体系组分间吸收光谱的线性独立性。利用数值稳定性较强的约束优化算法－可变容差法处理光谱数据,对不同浓度比例的七组分轻稀土混合物体系（Ｌａ＾３＋,Ｃｅ＾３＋,Ｐｒ＾３＋,Ｎｄ＾３＋,Ｓｍ＾３＋,Ｅｕ＾３＋,Ｇｄ＾３＋）的测定,取得     

Spectroscopic properties of Tm3+/Ho3+ co-doped NaLa(WO4)2 single crystal

Tm³⁺/Ho³⁺ co-doped NaLa(WO₄)₂ single crystal was successfully grown by the Czochralski method. The crystal was characterized by room temperature absorption spectra, fluorescence spectra around 2 μm, up-conversion fluorescence and luminescence decay measurements. Spectroscopic properties related to the laser operation around 2 μm of Ho³⁺ ions have been evaluated. The energy level scheme and energy transfer processes of Tm³⁺ and Ho³⁺ were analyzed. The obtained spectroscopic results show the crystal is a potentially host for Ho³⁺ 2 μm infrared laser.     

Photoluminescence of rare-earth ion(Eu~(3+), Tm~(3+), and Er~(3+))-doped and co-doped ZnNb_2O_6 for solar cells

Visible converted emissions produced at an excitation of 286 nm in Zn Nb2O6 ceramics doped with rare-earth ions(RE= Eu3+, Tm3+, Er3+or a combination of these ions) were investigated with the aim of increasing the photovoltaic efficiency of solar cells. The structure of RE:Zn Nb2O6 ceramics was confirmed by x-ray diffraction patterns. The undoped Zn Nb2O6 could emit a blue emission under 286-nm excitation, which is attributed to the self-trapped excitons' recombination of the efficient luminescence centers of edge-shared Nb O6 groups. Upon 286-nm excitation, Eu:Zn Nb2O6, Tm:Zn Nb2O6, and Er:Zn Nb2O6 ceramics showed blue, green, and red emissions, which correspond to the transitions of5D0→7FJ(J = 1–4)(Eu3+),1G4→3H6(Tm3+), and2H11/2/4S3/2→4I15/2(Er3+), respectively. The calculated CIE chromaticity coordinates of Eu:Zn Nb2O6, Tm:Zn Nb2O6, and Er:Zn Nb2O6are(0.50, 0.31),(0.14, 0.19), and(0.29, 0.56), respectively. RE ionco-doped Zn Nb2O6 showed a combination of characteristic emissions. The chromaticity coordinates of Eu/Tm:Zn Nb2O6,Eu/Er:Zn Nb2O6, and Tm/Er:ZnNb2O6 were calculated to be(0.29, 0.24),(0.45, 0.37), and(0.17, 0.25).     

Y3Al5O12:Ce3+,Cr3+和Y3Al5O12:Ce3+,pr3+,Cr3+荧光粉体系中的能量传递

通过在YAG:Ce3+和YAG:Ce3+,pr3+荧光粉体系中分别掺入Cr3+离子来提高蓝光管芯白光LED的显色指数.Cr3+离子的加入,增加了红光发射,这归因于Cr3+的2E-4 A2跃迁的零声子线和声子边带发光.Ce3+→Cr3+的能量传递是增强红光发射的重要方式,在YAG:Ce3+,Cr3+体系中,由发射光谱得到...     

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.     

可见分光光度法研究In3+与Zr4+、Ce3+、Rh3+和Ga3+的浮选分离

用可见分光光度法研究了溴化四丁基铵-碘化钾-水体系浮选分离铟的行为,探讨了In3+与-些金属离子分离的条件.结果表明,当溶液中溴化四丁基铵和碘化钾的浓度分别为6.0×10-4mol/L和5.0×10-3mol/L时,In3+与Zp+、Ce3+、Rh3+和Ga3+可定量分离.     

Up-conversion luminescence properties and energy transfer of Er~(3+)/Yb~(3+)co-doped oxyfluoride glass ceramic containing CaF_2 nano-crystals

The Er3+/Yb3+co-doped transparent oxyfluoride glass-ceramics containing CaF2nano-crystals were successfully prepared. After heat treatments, transmission electron microscopy(TEM) images showed that CaF2nano-crystals of 20–30 nm in diameter precipitated uniformly in the glass matrix. Comparing with the host glass, high efficiency upconversion luminescence of Er3+at 540 nm and 658 nm was observed in the glass ceramics under the excitation of 980 nm. Moreover,the size of the precipitated nano-crystals can be controlled by heat-treatment temperature and time. With the increase of the nano-crystal size, the intensity of the red emission increased more rapidly than that of the green emission. The energy transfer process of Er3+and Yb3+was convinced and the possible mechanism of Er3+up-conversion was discussed.     

Structure and up-conversion luminescence of Pr~(3+)/Yb~(3+) co-doped Ca Nb_2O_6 thin films by pulsed laser deposition

Pr3t∕Yb3tco-doped Ca Nb2O6 thin films are deposited on Si(100) substrates by pulsed laser deposition and annealed at different temperatures in air atmosphere. X-ray diffraction, Raman spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and photoluminescence spectra are used to characterize the samples. The results show that the annealing temperature has a strong effect on the film's grain size, structure,morphology, and the up-conversion luminescence properties. The grain size and up-conversion luminescence of Pr3t∕Yb3tco-doped Ca Nb2O6 films increases with the increasing annealing temperature.     

Optical properties of Mg~(2+),Yb~(3+),and Ho~(3+) tri-doped LiNbO_3 crystals

A series of LiNbO_3 crystals tri-doped with Mg~(2+),Yb~(3+),and Ho~(3+) are grown by the conventional Czochraski technique.The concentrations of Mg~(2+),Yb~(3+),and Ho~(3+) ions in Mg:Yb:Ho:LiNbO_3 crystals are measured by using an inductively coupled plasma atomic emission spectrometry.The x-ray diffraction is proposed to determine the lattice constant and analyze the internal structure of the crystal.The light-induced scattering of Mg:Yb:Ho:LiNbO_3 crystal is quantitatively described via the threshold effect of incident exposure energy flux.The exposure energy(E_r) is calculated to discuss the optical damage resistance ability.The exposure energy of Mg(7 mol):Yb:Ho:LiNbO3 crystal is 709.17 J/cm~2,approximately 425 times higher than that of the Mg(l mol):Yb:Ho:LiNbO_3 crystal in magnitude.The blue,red,and very intense green bands of Mg:Yb:Ho:LiNbO_3 crystal are observed under the 980-nm laser excitation to evaluate the up-conversion emission properties.The dependence of the emission intensity on pumping power indicates that the up-conversion emission is a two-photon process.The up-conversion emission mechanism is discussed in detail.This study indicates that Mg:Yb:Ho:LiNbO_3 crystal can be applied to the fabrication of new multifunctional photoluminescence devices.     

Er~(3+)和Yb~(3+)/Er~(3+)掺杂对石英光纤中倍频的影响

实验研究了掺Er~(3+)和Yb~(3+)/Er~(3+)石英光纤中的倍频过程.测量了不同Er~(3+)和Yb~(3+)/Er~(3+)掺杂量的光纤倍频转换效率和光纤倍频预处理前后Er~(3+)发射可见荧光的强度,探讨了Er~(3+)和Yb~(3+)掺杂对光纤中倍频过程的影响.     

硼碲酸盐玻璃材料中Er3+光谱性质对组分的依赖关系

采用熔融淬火技术制备了一组Er3+掺杂的变组分硼碲酸盐玻璃材料.测量了玻璃的折射率、吸收光谱及4I13/2→4I15/2跃迁的荧光寿命.利用标准的三参量Judd Ofelt理论对Er3+的光学跃迁性质进行了计算,并对Er3+离子的4I13/2能级的量子效率进行了研究.结果发现,随着样品中TeO2含量的增加样品的折射率变大,三个Judd Ofelt参量中Ω2随着样品组分的改变较明显,而另外两个参量Ω4和Ω6的变化较小.还发现随着TeO2含量的增加4I13/2→4I15/2辐射跃迁几率增大,并且该跃迁的量子效率增加.这一研究结果表明,在硼酸盐玻璃材料中引入TeO2可以有效地改善其中稀土离子的量子效率和辐射跃迁性能.     

LiYF4:Nd3+中脉冲光泵浦的上转换蓝光

本文报道利用578.4nm的脉冲光泵浦,在室温和77K下,观察到LiYF4:Nd3+单晶中的上转换蓝光。由发光强度与泵浦光强度平方的直线关系,确定此上转换过程是双光子过程.通过对吸收谱和激发谱以及衰减曲线的研究,确定其上转换激发机制为两步激发和能量传递上转换。     

Diode-pumped self-Q-switched single-frequency 946-nm Nd(3+), Cr(4+):YAG microchip laser

A stable low-threshold self-Q-switched diode-pumped 946-nm Nd(3+), Cr(4+):YAG microchip laser operating in single frequency and fundamental transverse mode is reported. The output characteristics of the microchip laser were investigated under cw and pulsed pumping. By combination of the infrared microchip and an external frequency doubler, 473-nm pulses with a conversion efficiency of 18% were achieved.     

Polymer waveguide thermo-optical switch with loss compensation based on NaYF_4: 18% Yb~(3+), 2% Er~(3+) nanocrystals

A polymer waveguide thermo-optical switch with loss compensation based on NaYF_4: 18% Yb~(3+), 2% Er~(3+)nanocrystals, fabricated by traditional semiconductor processes, has been investigated. NaYF4: 18% Yb~(3+), 2% Er~(3+)nanocrystals were prepared by a pyrolysis method. The morphology and luminescent properties of the nanocrystals were characterized.The nanocrystals were doped into SU-8 as the core material of an optical waveguide amplifier. The size of the device was optimized for its optical and thermal fields as well as its transmission characteristics. The device was fabricated on a silica substrate by spin coating, photolithography, and wet etching. The insertion loss of the switch device is～15 dB. The rise and fall times of the device are 240 μs and 380 μs, respectively, as measured by application of a 304 Hz square wave voltage. The extinction ratio of the device is about 14 dB at an electrode-driving power of 7 mW. When the pump light power is 230 mW and the signal light power is 0.1 mW, the loss compensation of the device is 3.8 dB at a wavelength of1530 nm. Optical devices with loss compensation have important research significance.