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测量了Tm3+离子不同浓度(0.5at.%, 3 at.%, 5 at.%)掺杂的NaY(WO4)2晶体在800nm激光二极管激发下的上转换发射光谱.结合吸收谱、荧光谱和由Judd-Ofelt理论计算的光谱参数,详细分析了Tm3+:NaY(WO4)2晶体中上转换能量传递机理和离子浓度对上转换发射的影响.讨论了四种影响上转换发光效率的离子间相互作用机理:3H5+1G4→3H6+1D2,3H5+3H5→3H6+3F3,1G4+3H6→3F4+3F3,1G4+3H6→3F3+3F4,并根据Miyakawa-Dexter理论定量计算了各过程的发生概率.论证了交叉弛豫和共协上转换等浓度猝灭效应是影响Tm3+离子蓝色上转换荧光发射效率的主要因素.
关键词:
3+离子')" href="#">Tm3+离子
4)2晶体')" href="#">NaY(WO4)2晶体
上转换
浓度猝灭 相似文献
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采用水热法合成了不同粒径的NaLa(MoO4)2∶Eu3+微晶.通过调节乙二醇浓度和反应时间,研究了NaLa(MoO4)2∶Eu3+微晶的形貌演变过程,在水热条件下180 ℃反应16 h获得了均一梭子形NaLa(MoO4)2∶Eu3+微晶,其晶粒长度约为2.0 μm.荧光光谱分析表明,Eu3+取代了NaLa(MoO4)2中La3+的格位, Eu3+在613 nm处红光发射(5D0–7F2跃迁)的浓度猝灭机理是电偶极-电四极相互作用,并发生了Eu3+( 5D1 ) + Eu3+(7F0 )→ Eu3+( 5D0 ) + Eu3+(7F3) 交叉弛豫,由此导致浓度猝灭.
关键词:
钼酸盐
水热法
稀土离子
发光 相似文献
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本工作测量了室温下TbP3O14和EuP5O14晶体的吸收和发射光谱。根据吸收光谱和Judd-Ofelt理论计算了Tb3+和Eu3+的实验和理论的振子强度。用最小二乘法拟合实验与理论的振子强度得到唯象强度参量Ωλ。然后计算了Tb3+的5D3→7F5,5D4→7F4和5D4→7F6以及Eu3+的5D0→7F2,5D0→7F4的跃迁几率和寿命。同时用时间分辨光谱测量了不同温度下相应的荧光辐射寿命。计算与实验结果基本相符。理论和实验的结果表明Tb3+的5D3态的寿命主要取决于5D3→5D4和7F6→7F0两能级对之间的电偶极-电偶极交叉弛豫。
关键词: 相似文献
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报道在超声射流冷却条件下用同步辐射VUV光源研究CH2Br2的振动自电离结构.根据测量的105—123nm范围内母体离子(CH2Br2+)的光电离产率曲线,获得CH2Br2的绝热电离势为10.23±0.01eV.CH2Br2+的最低三个电子激发态,即A(2A2),B(2B1),C(2A1)分别位于10.78±0.01eV,11.20±0.01eV和11.27±0.01eV.在115.01—121.15nm范围内,观察到CH2Br2自电离峰叠加在若干台阶结构上,台阶平均宽度为716.8±40.0cm-1,对应于CH2Br2+(X2B2)中Br-C-Br反对称的伸缩振动(v9),所有的峰均归属为收敛于CH2Br2+(X2B2,v+)振动能级的ns,np和nd自电离Rydberg态.此外,对CH2Br2光解离电离产生离子型自由基CH2Br+(X)的光电离产率曲线的结构也进行了归属
关键词: 相似文献
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以三种新合成的钌配合物[Ru(bpy)2(7-CH3-dppz)]2+、[Ru(bpy)2(7-F-dppz)]2+、[Ru(phen)2(7-F-dppz)]2+为研究对象,采用时间分辨的荧光光谱技术分别测量了这三种钌配合物与小牛胸腺DNA相互作用时的瞬态荧光动力学过程。结果表明:[Ru(bpy)2(7-CH3-dppz)]2+的发光寿命最长(约382 ns),而[Ru(bpy)2(7-F-dppz)]2+的发光寿命最短(约65 ns)。分析表明:钌配合物的发光来源于配合物分子中的电荷转移态到基态的辐射跃迁。通过钌配合物与DNA的相互作用,使得配合物激发态分子的无辐射弛豫几率减小,从而导致发光寿命的增加。配合物的分子与DNA相互作用越强,激发态分子的无辐射弛豫几率越小,发光寿命也越长,最终导致高的发光效率。配合物的分子结构对配合物的分子与DNA的相互作用具有重要的影响。 相似文献
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Weijie Guo Yanfu Lin Yujin Chen Yidong Huang 《Journal of Physics and Chemistry of Solids》2008,69(1):8-15
A Pr3+-doped KY(MoO4)2 single crystal was grown by the Czochralski method. The polarized absorption and fluorescence spectra of the Pr3+:KY(MoO4)2 crystal were measured at room temperature. The stimulated emission cross-sections for the transitions from the 3P0 multiplet were estimated from the fluorescence spectra. The fluorescence lifetime of the 3P0 multiplet was estimated from the fluorescence decay curve at room temperature. The analysis of spectral properties shows that the Pr3+:KY(MoO4)2 crystal is a promising gain medium for visible lasers. 相似文献
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The polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay curves of Pr3+ ions in anisotropic PbWO4 single crystal, which was grown by the modified Bridgman method, were measured at room temperature. The standard and modified Judd–Ofelt theories, extended to anisotropic crystal, have been applied to analyze the spectra. The spectroscopic parameters, including the Judd–Ofelt intensity parameters t(t=2,4,6), spontaneous emission probabilities, fluorescence branching ratios, radiative lifetimes, stimulated emission cross sections, and fluorescence quantum efficiencies, were estimated. The good spectroscopic properties show the possible application of the Pr3+-doped PbWO4 crystal as solid-state and self-stimulated Raman laser materials. PACS 78.20.-e; 42.70.Hj 相似文献
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F.B. Xiong X.H. Gong Y.F. Lin Y.J. Chen Q.G. Tan Z.D. Luo Y.D. Huang 《Applied physics. B, Lasers and optics》2007,86(2):279-286
A Pr3+-doped La2(WO4)3 crystal grown by the Czochralski method has been investigated as a promising laser material. The principal axes of the optical
indicatrix and Pr3+ concentration of the crystal were determined. The polarized absorption, fluorescence spectra and fluorescence decay curves
of the main emission multiplets of the crystal were measured at room temperature. The spectroscopic parameters were obtained
by the modified Judd–Ofelt theory combined with the normalized method. The peak stimulated emission cross-sections of the
major emission lines were estimated. The good spectroscopic properties imply that the Pr3+:La2(WO4)3 crystal is a potential laser gain medium for solid-state laser and self-stimulated Raman laser applications.
PACS 78.20.-e; 42.70.Hj 相似文献
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Impurity effect on the rare earth ion doped Sr0.6Ba0.4Nb2O6(SBN40) was studied at room temperature. Doping the rare earth ions of Pr3+ or Nd3+ changed the Raman profile: spectral broadening, central frequency shifts and relative intensity decreasing. Two reasons are considered according to the ferroelectric and optical properties of the rare earth ion doped SBN40: impurity-induced crystal disorder and the crystal structure change. SBN40 is the general disorder crystal and the disorder which is enhanced by doping the rare earth ion is especially strong along the x?y plane of the material compared with that along the polar C-axis. 相似文献
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Y.W. Xue X.H. Gong Y.F. Lin Z.D. Luo Y.D. Huang 《Applied physics. B, Lasers and optics》2008,91(3-4):455-459
A Bi2(MoO4)3 single crystal doped with Pr3+ ions has been grown by the Czochralski technique. The polarized absorption and fluorescence spectra as well as the fluorescence decay curve of Pr3+ ions in the crystal were measured at room temperature. The spectroscopic parameters, including the Judd–Ofelt intensity parameters Ωt (t=2, 4, and 6), spontaneous emission probabilities, fluorescence branching ratios, radiative lifetimes, stimulated emission cross sections, and fluorescence quantum efficiencies, were calculated. The spectral properties related to laser performance of this crystal were analyzed. The 1 D 2 multiplet of the crystal may be a good upper level for a solid-state laser. 相似文献
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The fluorescence lifetime τ1 of Pr3+ doped in the ferroelectric solid solution SNB40 (Ba0.4Sr0.6Nb2O6) was measured ar various temperatures. The fluorescence lifetime decreases gradually with increasing temperature. Furthermore, an anomalous increase of τ1 was observed at a specific temperature. The fluorescence linewidth and the peak wavelength of fluorescence also showed an anomalous change at this temperature. It is likely that this phenomenon is due to the phase transition of the host crystal SBN40. 相似文献
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Inverse Raman spectra of rare-earth ion doped SBN40 [Ba0.4Sr0.6Nb2O6:Pr3+(1.0 weight%)] are obtained over a range 0 to 950 cm?1 using an Ar ion laser and a pulse-dye laser with 0.2 micros pulsewidth. The spectra are in agreement with the results obtained by the normal Raman scattering. It is found that a single-shot IRS is possible to obtain the Raman spectrum within laser exposuring time, if it is a sharp one. 相似文献
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Z. Mazurak E. Łukowiak B. Jeżowska-Trzebiatowska D. Schultze Ch. Waligóra 《Journal of Physics and Chemistry of Solids》1984,45(5):487-493
Absorption and fluorescence spectra of LiPrP4O12 crystal were measured with high accuracy. Using the Judd-Ofelt theory the Ωλ parameters and probabilities of the radiative transitions for the 3P0, 1D2, excited states were calculated. From the presented analysis of the fluorescence spectra of Pr3+ ions, we conclude that there are two unequivalent positions in LiPrP4O12 crystals. 相似文献
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G. Stryganyuk G. Zimmerer N. Shiran V. Nesterkina K. Shimamura F. Jing A. Voloshinovskii 《Journal of luminescence》2008,128(12):1937-1941
Spectral-kinetic study of Pr3+ luminescence has been performed for LiLuF4:Pr(0.1 mol%) single crystal upon the excitation within 5-12 eV range at T=8 K. The fine-structure of Pr3+ 4f 2→4f 5d excitation spectra is shown for LiLuF4:Pr(0.1 mol%) to be affected by the efficient absorption transitions of Pr3+ ions into 4f 5d involving 4f 1 core in the ground state. Favourable conditions have been revealed in LiLuF4:Pr(0.1 mol%) for the transformation of UV-VUV excitation quanta into the visible range. Lightly doped LiLuF4:Pr crystals are considered as the promising luminescent materials possessing the efficient Pr3+3P0 visible emission upon UV-VUV excitation. The mechanism of energy transfer between Lu3+ host ion and Pr3+ impurity is discussed. 相似文献