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。     

稀土离子间反斯托克斯能量传递计算的改进 1.实验及理论基础

从理论和实验上研究了红绿荧光强度反转现象。实验测量发现Er(0.5)Yb(9.5)∶FOV纳米相氟氧化物玻璃陶瓷存在强的红绿荧光强度反转现象,实验测量得到其红绿荧光强度反转动态范围为877,同时计算了Er(0.5)Yb(9.5)∶FOV的所有基础光谱参量,建立了对系统所有稀土离子能级的动力学过程进行数值模拟计算的理论基础。     

纳米相氟氧化物玻璃陶瓷Tm（0.35）Yb（5）∶FOV的上转换发光

研究了纳米相氟氧化物玻璃陶瓷Tm(0.35)Yb(5)∶FOV在975nm半导体激光激发下的上转换发光。发现了位于363.6,(462.6,477.0),648.7,(699.7,680.7)和(777.6,800.7nm)的几条上转换发光线,它们是Tm3 离子的1D2→3H6,1G4→3H6,1G4→3F4,3F3→3H6和3H4→3H6的荧光跃迁。为了确认它们的上转换机理,还测量了上转换发光强度F随975nm泵浦激光功率P改变的双对数曲线,结果证实了1D2能级的上转换发光部分是五光子上转换发光,而1G4能级和3H4能级的上转换发光则是三光子和双光子上转换发光。     

BLUE COOPERATIVE UP-CONVERSION LUMINESCENCE OF Yb3+ IONS IN OXYFLUORIDE GLASS EXCITED BY 960 nm LASER

Investigates the up-conversion luminescence of Yb-doped oxyfluoride glass excited by a 960nm-diode laser. A new up-conversion cooperative radiation luminescence is found, which is rather strong and positioned at 476.1 nm. It comes from the coupled states of two-Yb^{3+-ions cluster. It is significant because it is an effective and convenient method of producing blue light.}     

Tm^3＋在氟氧化物玻璃陶瓷中的光普性质

根据Tm掺杂的氟氧化物玻璃陶瓷的吸收光谱,用Judd-Ofelt理论上计算了强度参量,并由此计算了激发能极的自发辐射跃迁几率、辐射寿命、荧光分支和积分发射截面等光谱参量。     

Multiphoton ultraviolet and visible upconversion luminescence of TmYb co-doped oxyfluoride glass

The ultraviolet upconversion luminescence of Tm³⁺ ions sensitized by Yb³⁺ ions in oxyfluoride glass when excited by a 975 nm diode laser was studied in this paper. One typical ultraviolet upconversion luminescence lines positioned at 362.3 nm was found. It can be attributed to the five-photon upconversion luminescence transition of ¹D₂ → ³H₆. Several visible upconversion luminescence lines at 451.1 nm, (477.9 nm, 462.5 nm), 648.7 nm, (680.5 nm, 699.5 nm) and (777.5 nm, 800.7 nm) were found also, which results from the fluorescence transitions of five-photon ¹D₂ → ³F₄, three-photon ¹G₄ → ³H₆, three-photon ¹G₄ → ³F₄, two-photon ³F₃ → ³H₆ and two-photon ³H₄ → ³H₆ of Tm³⁺ ion, respectively. The theoretical analysis suggests that the upconversion mechanism of the 362.3 nm ¹D₂ → ³H₆ upconversion luminescence is the cross energy transfer of {³H₄(Tm³⁺) → ³F₄(Tm³⁺), ¹G₄(Tm³⁺) → ¹D₂(Tm³⁺)} and {¹G₄(Tm³⁺) → ³F₄(Tm³⁺), ³H₄(Tm³⁺) → ¹D₂(Tm³⁺)} between Tm³⁺ ions. In addition, the upconversion luminescence of ¹G₄ and ³H₄ state results from the sequential energy transfer {²F_5/2(Yb³⁺) → ²F_7/2(Yb³⁺), ³H₄(Tm³⁺) → ¹G₄(Tm³⁺)} and {²F_5/2(Yb³⁺) → ²F_7/2(Yb³⁺), ³F₄(Tm³⁺) → ³F₂(Tm³⁺)} from Yb³⁺ ions to Tm³⁺ions, respectively.     

4-Diazomethyl-7-Methoxycoumarin as a New Type of Stable Aryldiazomethane Reagent

Diazoalkanes have been widely used as versatile alkylating agents. One of the principal advantages of using diazoalkane is that no side reaction product other than gaseous nitrogen is produced during alkylation process. However, most diazoalkanes suffer from the fact that they are unstable, sometimes explosive, and are not available in pure state. They have to be only used in the solutions prepared from appropriate precursors just before use. Thus, only a few compounds have been developed so far as solid diazoalkane reagents¹ of practical value which are suitable for labeling acidic substances for analytical and biochemical purposes. We have now obtained 4-diazomethyl-7-methoxycoumarin 4 as a new type of crystalline aryldiazomethane having excellent purity and stability as well as enough reactivity to produce a fluorophore with carboxylic or sulfonic acid by esterification.     

纳米相氟氧化物玻璃陶瓷Tm(0.35)Yb(5):FOV的上转换发光

研究了纳米相氟氧化物玻璃陶瓷Tm(0.35)Yb(5):FOV在975 nm半导体激光激发下的上转换发光.发现了位于363.6,(462.6,477.0),648.7,(699.7,680.7)和(777.6,800.7 nm)的几条上转换发光线,它们是Tm3 离子的1D2→H6,1G→H6,1G4→F4,3F3→H6和3H4→H6的荧光跃迁.为了确认它们的上转换机理,还测量了上转换发光强度F随975 am泵浦激光功率P改变的双对数曲线,结果证实了1D2能级的上转换发光部分是五光子上转换发光,而1G4能级和H4能级的上转换发光则是三光子和双光子上转换发光.     

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。     

掺钬镱离子的氟氧化物玻璃陶瓷的一级和二级红外量子剪裁的研究

本文报道了掺钬镱离子的氟氧化物玻璃陶瓷的一级和二级红外量子剪裁的比较研究．研究发现当0G5能级到0＆能级及之间的能级被激发的时候,大多数的粒子数容易无辐射弛豫到（5F4^5S2）能级．在（0F40＆）能级,由很强的ET7-ETaYb{5F4（Ho）→5I6（Ho）,2F7／2（Yb）→2F5/2（Yb））交叉能量传递渠道,导致Ho3＋离子的粒子数被无损耗的交叉能量传递到5I6能级,同时Yb3＋离子从基态2F7／2能级被激发到2F5/2能级,它导致了两个能被晶体硅有效吸收的红外光子,即一个（1153am,1188am）的红外光子和另一个（973．0nm,1002．0nm）的红外光子,因此出现了显著的双光子一级红外量子剪裁．最后,该文计算了Ho（0．5）Yb（1）：FOV和Ho（0．5）Yb（10．5）：FOV的交叉能量传递效率为ηtr,1％Yb（5FS2）=29．2％,‰,10．5％Yb（5F4^5S2）=99．2％和它们的共合作能量传递效率为ηtr,1％Yb（5F3）=4．18％,ηtr,10．5％Yb（5F3）=75．3％;而它们的双光子量子剪裁效率的理论上限值依次为ηCR,1％Yb（5F4^5S2）=129．2％,ηCR,10．5％Yb（5F4^5S2）=199．2％和ηCO,1％Yb（5F3）=104．18％,ηCO,10.5％Yb（5F3）=175．3％．因此发现了一级红外量子剪裁有比二级红外量子剪裁高较多的概率．该项研究对太阳能电池效率的提高很有意义．