稀土掺杂微纳材料中高阶多光子上转换发光及其电子布居过程的研究
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摘要
光频上转换是物理学中获得短波长发光十分重要的方法；对上转换发光材料及其机理的研究一直是固体发光领域的前沿和热点课题。蓝紫色和紫外上转换材料和器件在激光、通信、能源、医疗、催化和军事等领域都有着十分重要的应用前景。利用稀土离子具有的丰富能级,原则上人们可以通过上转换的方式将不同低能频域的光转换为所需要的高能量光子,以满足实际应用中的需要。目前,有关红外光激发下的上转换发光的研究主要集中在可见波段,而紫外上转换发光的研究相对较少。究其原因,主要是由于上转换过程中低的转换效率造成的。上转换过程的这个特点导致实验中获得的上转换发光大多来自两光子或三光子过程,有些材料在高的激发功率的激发下可能出现弱的四光子上转换发光。但是更高阶数的上转换过程却不容易被观测到,上转换发光的这个特点严重地限制了它在很多领域中的应用。针对上述问题,本文以具有优异上转换发光性能的六角相NaYF4为研究对象,首次获得了部分稀土离子的高阶多光子上转换发光。同时,我们围绕高阶多光子上转换发光过程中光与物质相互作用这一基本科学问题,从稳态光谱到荧光动力学过程、从电子跃迁与晶格弛豫到能量传递、从上转换材料到其中的物理机制,展开了系统的研究并取得了一些创新性的研究结果。另外,在稀土上转换白光材料方面,我们也取得了创新性的成果,主要结果如下：
1、用水热法合成了NaYF4:Yb3+/Er3+微米晶。在近红外光激发下,发现了样品中Er3+离子覆盖近红外到紫外波段的上转换发光,首次观察到了Er3+离子的五光子和六光子上转换发光过程。首次在实验上证明了室温下Er3+离子红光发射的三光子过程。动力学分析的结果证明了共掺杂体系中Yb3+到Er3+离子的能量传递过程。Yb3+到Er3+离子的持续的能量传递是布居高能态Er3+离子的关键。探讨了Er3+离子高能态布居的功率密度依赖特性,与低功率密度激发相比,在高的激发光功率密度激发下Er3+离子的紫外发射来自于更高阶的上转换过程。来自Er3+离子2I11/2和4D7/2能级的上转换发光表现出功率和温度依赖特性,证明了存在于两能级间的多声子弛豫过程。
2、用水热法合成了NaYF4:Yb3+/Er3+/Gd3+和NaYF4:Yb3+/Tm3+/Gd3+微米晶。在980 nm激光激发下,首次在NaYF4基质中观察到了Gd3+离子的紫外上转换发光。Er3+离子和Tm3+离子在两个共掺杂体系中分别起到稀土离子间能量传递的“桥联”作用；Er3+和Tm3+离子到Gd3+离子的有效的能量传递是布居激发态Gd3+离子的关键。浓度变化实验及动力学分析的结果证明了Er3+和Tm3+离子到Gd3+离子的能量传递并给出了一些可能的能量传递途径。功率依赖的发光强度分析表明980 nm激光激发下共掺杂体系中Gd3+离子的上转换发光来自于五光子和六光子上转换过程。
3、在红外光(1560 nm)激发下,在NaYF4:Yb3+/Er3+微米晶中首次观察到了Er3+离子的紫外(244 nm,256 nm,276 nm,288 nm,306 nm,317 nm和335 nm)上转换发光。光谱分析证实了存在于Er3+和Yb3+离子之间的能量传递过程。Er3+离子的激发态吸收和Yb3+到Er3+离子的能量传递是布居高能态Er3+离子的两个重要途径。红外光激发下Er3+离子的紫外发射来自高阶上转换过程,功率依赖的发光强度分析指出了迄今为止有记录的最高阶的上转换过程——十一光子过程。
4、在1560 nm激光激发下,在β-NaYF4:Yb3+/Gd3+/Er3+微米晶中首次观测到了Gd3+离子的紫外(276.8 nm,279.6 nm,306 nm和311 nm)上转换发光。Er3+离子在共掺杂体系中的“桥联”作用是布居高能态Gd3+离子的关键因素。光谱分析和动力学分析结果证明了Er3+到Gd3+离子的能量传递。Gd3+离子61J多重态内相邻能级间的布居由热布居决定。发光强度与功率依赖关系证明了Gd3+离子的上转换发光来自八光子和九光子过程。
5、用湿化学方法伴随后退火的方法合成了稀土离子掺杂的Gd2O3纳米管。扫描电镜结果证明了样品管状结构的形成。在980 nm近红外光激发下,首次在Gd203基质材料中获得了室温下明亮的上转换白色发光。当980 nm激光二极管激发功率密度在很大范围内变化时,利用样品上转换发射谱计算得到的色坐标值变化很小,并全部位于1931色度图白色区域内,证明样品是一种优异的白光材料。在Yb3+-Er3+-Tm3+共掺杂的Gd2O3纳米管中,白色上转换发光中的蓝光和绿光成分分别来自于Tm3+离子和Er3+离子的贡献,而红光发射来自于Er3+和Tm3+离子的共同贡献。蓝色,绿色和红色上转换发光分别来自于两光子和三光子过程。动力学分析证明了存在于Tm3+离子和Er3+离子间的能量传递过程。
Frequency upconversion is one of the major routes for achieving short-wavelength light. The studies around upconversion luminescence materials and upconversion mechanism became research focus in the past decades. Blue, violet, and ultraviolet upconversion luminescence have been widely investigated throughout the scientific community owing to great fundamental interests and numerous applications in the fields of laser, communication, energy, medical treatment, photocatalysis, military, etc. Multiphoton upconversion is an anti-stokes process, which can convert low energy photon to high energy photon for satisfying requirements of real applications. Up to now, most studies about rare earth upconversion were limited in visible portion, and only a few papers have reported their ultraviolet upconversion luminescence. All these can attribute to the low transform efficiency during upconversion processes. Most upconversion luminescence of rare earth ions in the experiments came from two-photon or three-photon process, and some materials may present weak four-photon upconversion process under high power light excitation. However, higher-order upconversion processes are difficult to obtain. This bottleneck severely limited the use of upconversion technology in many fields. In view of the above questions, hexagonal NaYF4, with good upconversion performance, was selected as research subject in this paper. High-ordre multiphoton upconversion luminescence of some rare-earth ions were obtained firstly in our experiments. The light-matter interaction, electron transition, lattice relaxation, energy transfer, multiphoton upconversion luminescence and its interior mechanism in rare-earth ions doped materials were studied systematically through laser spectroscopic measurements and dynamic analysis and some of innovative results were obtained. Additionally, innovative research results were obtained in the field of rare-earth doped white upconversion luminescence. The major achievements obtained are as follow:
1. NaYF4:Yb3+/Er3+microcrystals were prepared by using hydrothermal method. Under near-infrared light excitation, near-infrared to ultraviolet upconversion luminescence of Er3+were observed. Five-photon and six-photon upconversion processes of Er3+were obtained for the first time. Three-photon upconversion process of red emission of Er3+were confirmed experimentally for the first time. In Yb3+-Er3+ codoped system, energy transfer from Yb3+to Er3+played important roles in populating high-energy excited states of Er+. The power density-dependent populating processes of Er3+were discussed. Compared with low power density excitation, the ultraviolet emissions of Er3+came from higher-order processes under high power density excitation. The ultraviolet emissions came from 2I11/2 and 4D7/2 states of Er3+present power and temperature dependence, which demonstrated the existence of nonradiative relaxation process between these two states.
2. NaYF4:Yb3+/Er3+/Gd3+and NaYF4:Yb3+/Tm3+/Gd3+microcrystals were prepared by using hydrothermal method. Under 980 nm excitation, ultraviolet upconversion luminescence of Gd3+were observed firstly in NaYF4 matrix. In the codoped system, Er3+and Tm3+act as "bridging" ions during energy transfer processes. Energy transfers from Er3+to Gd3+ions and from Tm3+to Gd3+ions played important roles in populating excited Gd3+. Experiments on concentration variation and dynamic analysis revealed the energy transfer processes between Er3+and Gd3+ and between Tm3+and Gd3+. Some of possible energy transfer routes were proposed based on experimental results. Power dependence of luminous intensity revealed the upconversion emissions of Gd3+came from five-photon and six-photon processes.
3. Under 1560 nm infrared light excitation, ultraviolet (244 nm,256 nm,276 nm, 288 nm,306 nm,317 nm, and 335 nm) upconversion emissions of Er3+were observed firstly in NaYF4:Yb3+/Er3+microcrystals. Energy transfers between Er3+and Yb3+ were confirmed by spectral analysis. Excited state absorption of Er3+and energy transfers from Yb3+to Er3+are two major routes in populating high-energy excited states of Er3+. Ultraviolet emissions of Er3+came from high-order multiphoton upconversion processes. The highest-order upconversion process—eleven-photon upconversion process was observed in our experiments.
4. Under 1560 nm excitation, ultraviolet (276.8 nm,279.6 nm,306 nm, and 311 nm) upconversion emissions of Gd3+were observed firstly inβ-NaYF4:Yb3+/Gd3+/Er3+microcrystals. In the codoped system, the "bridging" effect of Er3+played important roles in populating high-energy states of Gd3+ions. Energy transfers from Er3+to Gd3+were confirmed by spectral analysis and dynamic analysis. The thermal population between 6IJ multiplet is the main mode in producing their neighboring states. Power dependence of luminous intensity demonstrated the eight-photon and nine-photon upconversion processes of Gd3+.
5. Rare-earth ions doped Gd2O3 nanotubes were synthesized by using a simple wet-chemical route at low temperature and ambient pressure followed by a subsequent heat treatment. SEM results depicted the hollow and tubular column feature of the nanotubes clearly. Under 980 nm excitation, room-temperature upconversion white luminescence was achieved in Gd2O3 matrix for the first time. The calculated CIE color coordinates fall well within the white region and shift only slightly when the power density changed in a wide region. In the Yb3+-Er3+-Tm3+codoped Gd2O3 nanotubes, blue and green upconversion emissions came from Tm3+and Er3+ respectively. Both Tm3+and Er3+ are effective to induce the red upconversion luminescence. Blue, green and red upconversion luminescence came from two-photon and three-photon processes, respectively. Dynamic analysis revealed the energy transfer from Tm3+ to Er3+ clearly.
1、用水热法合成了NaYF4:Yb3+/Er3+微米晶。在近红外光激发下,发现了样品中Er3+离子覆盖近红外到紫外波段的上转换发光,首次观察到了Er3+离子的五光子和六光子上转换发光过程。首次在实验上证明了室温下Er3+离子红光发射的三光子过程。动力学分析的结果证明了共掺杂体系中Yb3+到Er3+离子的能量传递过程。Yb3+到Er3+离子的持续的能量传递是布居高能态Er3+离子的关键。探讨了Er3+离子高能态布居的功率密度依赖特性,与低功率密度激发相比,在高的激发光功率密度激发下Er3+离子的紫外发射来自于更高阶的上转换过程。来自Er3+离子2I11/2和4D7/2能级的上转换发光表现出功率和温度依赖特性,证明了存在于两能级间的多声子弛豫过程。
2、用水热法合成了NaYF4:Yb3+/Er3+/Gd3+和NaYF4:Yb3+/Tm3+/Gd3+微米晶。在980 nm激光激发下,首次在NaYF4基质中观察到了Gd3+离子的紫外上转换发光。Er3+离子和Tm3+离子在两个共掺杂体系中分别起到稀土离子间能量传递的“桥联”作用；Er3+和Tm3+离子到Gd3+离子的有效的能量传递是布居激发态Gd3+离子的关键。浓度变化实验及动力学分析的结果证明了Er3+和Tm3+离子到Gd3+离子的能量传递并给出了一些可能的能量传递途径。功率依赖的发光强度分析表明980 nm激光激发下共掺杂体系中Gd3+离子的上转换发光来自于五光子和六光子上转换过程。
3、在红外光(1560 nm)激发下,在NaYF4:Yb3+/Er3+微米晶中首次观察到了Er3+离子的紫外(244 nm,256 nm,276 nm,288 nm,306 nm,317 nm和335 nm)上转换发光。光谱分析证实了存在于Er3+和Yb3+离子之间的能量传递过程。Er3+离子的激发态吸收和Yb3+到Er3+离子的能量传递是布居高能态Er3+离子的两个重要途径。红外光激发下Er3+离子的紫外发射来自高阶上转换过程,功率依赖的发光强度分析指出了迄今为止有记录的最高阶的上转换过程——十一光子过程。
4、在1560 nm激光激发下,在β-NaYF4:Yb3+/Gd3+/Er3+微米晶中首次观测到了Gd3+离子的紫外(276.8 nm,279.6 nm,306 nm和311 nm)上转换发光。Er3+离子在共掺杂体系中的“桥联”作用是布居高能态Gd3+离子的关键因素。光谱分析和动力学分析结果证明了Er3+到Gd3+离子的能量传递。Gd3+离子61J多重态内相邻能级间的布居由热布居决定。发光强度与功率依赖关系证明了Gd3+离子的上转换发光来自八光子和九光子过程。
5、用湿化学方法伴随后退火的方法合成了稀土离子掺杂的Gd2O3纳米管。扫描电镜结果证明了样品管状结构的形成。在980 nm近红外光激发下,首次在Gd203基质材料中获得了室温下明亮的上转换白色发光。当980 nm激光二极管激发功率密度在很大范围内变化时,利用样品上转换发射谱计算得到的色坐标值变化很小,并全部位于1931色度图白色区域内,证明样品是一种优异的白光材料。在Yb3+-Er3+-Tm3+共掺杂的Gd2O3纳米管中,白色上转换发光中的蓝光和绿光成分分别来自于Tm3+离子和Er3+离子的贡献,而红光发射来自于Er3+和Tm3+离子的共同贡献。蓝色,绿色和红色上转换发光分别来自于两光子和三光子过程。动力学分析证明了存在于Tm3+离子和Er3+离子间的能量传递过程。
Frequency upconversion is one of the major routes for achieving short-wavelength light. The studies around upconversion luminescence materials and upconversion mechanism became research focus in the past decades. Blue, violet, and ultraviolet upconversion luminescence have been widely investigated throughout the scientific community owing to great fundamental interests and numerous applications in the fields of laser, communication, energy, medical treatment, photocatalysis, military, etc. Multiphoton upconversion is an anti-stokes process, which can convert low energy photon to high energy photon for satisfying requirements of real applications. Up to now, most studies about rare earth upconversion were limited in visible portion, and only a few papers have reported their ultraviolet upconversion luminescence. All these can attribute to the low transform efficiency during upconversion processes. Most upconversion luminescence of rare earth ions in the experiments came from two-photon or three-photon process, and some materials may present weak four-photon upconversion process under high power light excitation. However, higher-order upconversion processes are difficult to obtain. This bottleneck severely limited the use of upconversion technology in many fields. In view of the above questions, hexagonal NaYF4, with good upconversion performance, was selected as research subject in this paper. High-ordre multiphoton upconversion luminescence of some rare-earth ions were obtained firstly in our experiments. The light-matter interaction, electron transition, lattice relaxation, energy transfer, multiphoton upconversion luminescence and its interior mechanism in rare-earth ions doped materials were studied systematically through laser spectroscopic measurements and dynamic analysis and some of innovative results were obtained. Additionally, innovative research results were obtained in the field of rare-earth doped white upconversion luminescence. The major achievements obtained are as follow:
1. NaYF4:Yb3+/Er3+microcrystals were prepared by using hydrothermal method. Under near-infrared light excitation, near-infrared to ultraviolet upconversion luminescence of Er3+were observed. Five-photon and six-photon upconversion processes of Er3+were obtained for the first time. Three-photon upconversion process of red emission of Er3+were confirmed experimentally for the first time. In Yb3+-Er3+ codoped system, energy transfer from Yb3+to Er3+played important roles in populating high-energy excited states of Er+. The power density-dependent populating processes of Er3+were discussed. Compared with low power density excitation, the ultraviolet emissions of Er3+came from higher-order processes under high power density excitation. The ultraviolet emissions came from 2I11/2 and 4D7/2 states of Er3+present power and temperature dependence, which demonstrated the existence of nonradiative relaxation process between these two states.
2. NaYF4:Yb3+/Er3+/Gd3+and NaYF4:Yb3+/Tm3+/Gd3+microcrystals were prepared by using hydrothermal method. Under 980 nm excitation, ultraviolet upconversion luminescence of Gd3+were observed firstly in NaYF4 matrix. In the codoped system, Er3+and Tm3+act as "bridging" ions during energy transfer processes. Energy transfers from Er3+to Gd3+ions and from Tm3+to Gd3+ions played important roles in populating excited Gd3+. Experiments on concentration variation and dynamic analysis revealed the energy transfer processes between Er3+and Gd3+ and between Tm3+and Gd3+. Some of possible energy transfer routes were proposed based on experimental results. Power dependence of luminous intensity revealed the upconversion emissions of Gd3+came from five-photon and six-photon processes.
3. Under 1560 nm infrared light excitation, ultraviolet (244 nm,256 nm,276 nm, 288 nm,306 nm,317 nm, and 335 nm) upconversion emissions of Er3+were observed firstly in NaYF4:Yb3+/Er3+microcrystals. Energy transfers between Er3+and Yb3+ were confirmed by spectral analysis. Excited state absorption of Er3+and energy transfers from Yb3+to Er3+are two major routes in populating high-energy excited states of Er3+. Ultraviolet emissions of Er3+came from high-order multiphoton upconversion processes. The highest-order upconversion process—eleven-photon upconversion process was observed in our experiments.
4. Under 1560 nm excitation, ultraviolet (276.8 nm,279.6 nm,306 nm, and 311 nm) upconversion emissions of Gd3+were observed firstly inβ-NaYF4:Yb3+/Gd3+/Er3+microcrystals. In the codoped system, the "bridging" effect of Er3+played important roles in populating high-energy states of Gd3+ions. Energy transfers from Er3+to Gd3+were confirmed by spectral analysis and dynamic analysis. The thermal population between 6IJ multiplet is the main mode in producing their neighboring states. Power dependence of luminous intensity demonstrated the eight-photon and nine-photon upconversion processes of Gd3+.
5. Rare-earth ions doped Gd2O3 nanotubes were synthesized by using a simple wet-chemical route at low temperature and ambient pressure followed by a subsequent heat treatment. SEM results depicted the hollow and tubular column feature of the nanotubes clearly. Under 980 nm excitation, room-temperature upconversion white luminescence was achieved in Gd2O3 matrix for the first time. The calculated CIE color coordinates fall well within the white region and shift only slightly when the power density changed in a wide region. In the Yb3+-Er3+-Tm3+codoped Gd2O3 nanotubes, blue and green upconversion emissions came from Tm3+and Er3+ respectively. Both Tm3+and Er3+ are effective to induce the red upconversion luminescence. Blue, green and red upconversion luminescence came from two-photon and three-photon processes, respectively. Dynamic analysis revealed the energy transfer from Tm3+ to Er3+ clearly.
引文
[1]Hebert T, Wannemacher R, Macfarlane R M, et al. Blue continuously upconversion lasing in Tm:LiYF4 [J]. Appl. Phys. Lett.,1992,60:2592-2594.
[2]J. Y. Allain, M. Monerie, and H. Poignant. Tunable green upconversion erbium fiber laser [J]. Electron. Lett.,1992,28:111
[3]Heine F, Heumann E, Danget T, et al. Green upconversion continuous wave Er3+ LiYF4 laser at room temperature [J]. Appl. Phys. Lett.,1994,65(4):383-385.
[4]El-Agmy R M. Upconversion CW laser at 284 nm in a Nd:YAG-pumped double-cladding thulium-doped ZBLAN fiber laser [J]. Laser Phys.,2008,18: 803.
[5]Zhao Y, Fleming S. All-solid state and all-fiber blue upconversion laser [J]. Electron. Lett.,1996,32:1199-1200.
[6]Liu X M, Jia P Y, Lin J, et al. Monodisperse spherical core-shell structured SiO2-CaTiO3:Pr3+phosphors for field emission displays [J]. J. Appl. Phys.,2006, 99(12):124902-124902(7).
[7]Milliez J, Rapaport A, Bass M, et al. High-Brightness White-Light Source Based on Up-Conversion Phosphors [J]. J. Display Technol.2006,2(3):307-311.
[8]Downing E, Hesselink L, Ralston J, et al. A three-color, solid-state, three-dimensional display [J]. Science,1996,273:1185-1189.
[9]Yang Z M, Feng Z M, and Jiang Z H. Upconversion emission in multi-doped glasses for full colour display [J]. J Phys D Appl Phys,2005,38:1629-1632.
[10]Maciel G S, Biswas A, Kapoor R, et al. Blue cooperative upconversion in Yb3+-doped multicomponent sol-gel-processed silica glass for three-dimensional display [J]. Appl. Phys. Lett.,2000,76:1978-1980.
[11]Jiang S, Zhang Y, Lim K M, et al. NIR-to-visible upconversion nanoparticles for fluorescent labeling and targeted delivery of siRNA [J]. Nanotechnology 2009, 20:155101.
[12]Xiong L Q, Chen Z G, Tian Q W, et al. High Contrast Upconversion Luminescence Targeted Imaging in Vivo Using Peptide-Labeled Nanophosphors [J]. Anal Chem.,2009,81:8687-8694.
[13]Wang C, Cheng L A, and Liu Z A. Drug delivery with upconversion nanoparticles for multi-functional targeted cancer cell imaging and therapy [J]. Biomaterials,2011,32:1110-1120.
[14]Kamimura M, Miyamoto D, Saito Y, et al. Design of poly(ethylene glycol)/streptavidin coimmobilized upconversion nanophosphors and their application to fluorescence biolabeling [J]. Langmuir,2008,24:8864-8870.
[15]Wang M, Mi C C, Wang W X, et al. Immunolabeling and NIR-Excited Fluorescent Imaging of HeLa Cells by Using NaYF4:Yb, Er Upconversion Nanoparticles [J]. Acs Nano,2009,3:1580-1586.
[16]Ahrens B, Loper P, Goldschmidt J C, et al. Neodymium-doped fluorochlorozirconate glasses as an upconversion model system for high efficiency solar cells [J]. Phys Status Solidi A,2008,205:2822-2830.
[17]B S Richards, Avi Shalav. Enhancing the Near-infrared Spectral Response of Silicon Optoelectronic Devices via Up-conversion [J]. IEEE transaction on electron devices,2007,54:2679-2684.
[18]Ivanova S, Pelle F. Strong 1.53μm to NIR-VIS-UV upconversion in Er-doped fluoride glass for high-efficiency solar cells [J]. J Opt Soc Am B,2009,26: 1930-1938.
[19]A Shalav, B S Richards, and M A Green.d, Luminescent layers for enhanced silicon solar cell performance:Up-conversion [J]. Sol Energ Mat Sol C,2007,91: 829-842.
[20]de Wild J, Meijerink A, Rath J K, et al. Towards upconversion for amorphous silicon solar cells [J]. Sol Energ Mat Sol C,2010,94:1919-1922.
[21]Qin W P, Zhang D S, Zhao D, et al. Near-infrared Photocatalysis Based on YF3:Yb3+,Tm3+/TiO2 Core/shell Nanoparticles [J]. Chem. Commun,2010,46: 2304-2306.
[22]戎红仁,王平,顾浩.新型的防伪材料红外上转换材料[J].印刷杂志,2002,8：190-191.
[23]刘政威,佘仲明.能量上转换功能材料及其制作的防伪标记材料：中国,ZL00113404.3[P],2004.
[24]Auzel F, Comt. Rend, computeur quantique par transfer d'energie de Yb3+, Tm3+ dans an tungstate mixte et dans un VeiTe gemanate [J]. C. R. Acad. Sci. (Paris), 1966,263B:819-821.
[25]Auzel F, Upconversion and Anti-Stokes Processes with f and d Ions in Solids [J]. Chem. Rev.,2004,104:139.
[26]Pollnau M, Gamelin D R, Luthi S R, et al. Power dependence of upconversion luminescence in lanthanide and transition-metal-ion systems [J]. Phys. Rev. B, 2000,61:3337.
[27]Yang F Z, Yi G S, Chen D P, et al. Synthesis and up-conversion luminescence properties of nanocrystal Yb, Ho co-doped sodium yttrium fluoride [J]. Chem. J. Chinese. U.,2004,25:1589.
[28]Chen G, Liu H, Somesfalean G, et al. Upconversion emission tuning from green to red in Yb3+/Ho3+-codoped NaYF4 nanocrystals by tridoping with Ce3+ions [J]. Nanotechnology,2009,20:385704.
[29]Goh S C, Pattie R, Byrne C, et al. Blue and red laser action in Nd3+and Pr3+ co-doped fluorozirconate glass [J]. Appl. Phys. Lett.,1995,67(6):768-770.
[30]Zhang X, Serrano C, Daran E, et al. Infrared-laser-induced upconversion from Nd3+:LaF3 heteroepitaxial layers on CaF2(111) substrates by molecular beam epitaxy [J]. Phys. Rev. B,2000,62:4446-4454.
[31]Wada N, Kojim K. Dispersion and upconversion fluorescence of Nd3+ions in zinc chloride-based glasses [J]. J Am Ceram Soc,2002,85:590-594.
[32]Wang Y H, Junichi O, New transparent vitroceramics codoped with Er3+and Yb3+for efficient frequency upconversion [J]. Appl. Phys. Lett.,1993,63: 3268-3270.
[33]Man S O, Pun E Y B, Chung P S, Upconversion luminescence of Er3+in alkali bismuth gallate glasses [J]. Appl. Phys. Lett.,2000,77 (4):483-485.
[34]Song F, Su J, Tan H, et al. The energy transfer processes between the Er3+and Tm3+in Er, Tm-codoped-NaY(WO4)2 crystal [J]. Opt. Commun.,2004,241(4-6): 455-463.
[35]Jouart J P, Oomen E W J, Upconversion in Er3+-Doped Fluorite-Type Crystals Excited at 800 nm [J]. Phys. Stat. Sol. (b),1992,172 (1):461-470.
[36]Balda R, Garcia-Adeva A J, Voda M, et al. Upconversion processes in Er3+-doped KPb2Cl5 [J]. Phys. Rev. B,2004,69 (20):205203-205210.
[37]Hehlen M P, Kuditcher A, Lenef A L, et al. Nonradiative dynamics of avalanche upconversion in Tm:LiYF4 [J]. Phys. Rev. B,2000,61(2):1116-1128.
[38]Chen D Q, Wang Y S, Yu Y L, et al. Intense ultraviolet upconversion luminescence from Tm3+/Yb3+:YF3 nanocrystals embedded glass ceramic [J]. Appl. Phys. Lett.,2007,91:051920-051922.
[39]Martin I R, Mendez-Ramos J, Rodriguez V D, et al. Increase of the 800 nm excited Tm3+blue upconversion emission in fluoroindate glasses by codoping with Yb3+ions [J]. Opt. Mater.,2003,22 (4):327-333.
[40]Huang L H, Liu X R, Xu W, et al. Infrared and visible luminescence properties of Er3+and Yb3+ions codoped Ca3Al2Ge3O12 glass under 978 nm diode laser excitation [J]. J. Appl. Phys.,2001,90 (11):5550-5553.
[41]Qin G S, Qin W P, Huang S H, et al. Infrared-to-violet upconversion from Yb3+ and Er3+codoped amorphous fluoride film prepared by pulsed laser deposition [J]. J. Appl. Phys.,2002,92 (11):6936-6938.
[42]Y. Mita, K. Hirama, N. Ando, et al. Luminescence processes in Tm3+-and Er3+-ion-activated, Yb3+-ion-sensitized infrared upconversion devices [J]. J. Appl. Phys.,1993,74:4703.
[43]Thrash R J, Johnson L F, Upconversion laser emission from YbJ+-sensitized TmJ+ in BaY2F8[J]. J. Opt. Soc.Am. B.,1994,11(5):881-885.
[44]Higuchi H, Takahashi M, Kawamoto Y, et al. Optical transitions and frequency upconversion emission of Er3+ions in Ga2S3--GeS2--La2S3 glasses [J]. J. Appl. Phys.,1998,83:19.
[45]Dwivedi Y, Thakur S N, Rai S B. Study of frequency upconversion in Yb3+/Eu3+ by cooperative energy transfer in oxyfluoroborate glass matrix [J]. Appl. Phys. B-Lasers O.,2007,89:45.
[46]Huang L, Yamashita T, Jose R, et al. Intense ultraviolet emission from Tb3+and Yb3+codoped glass ceramic containing CaF2 nanocrystals [J]. Appl. Phys. Lett., 2007,90:131116.
[47]Hu Z J, Wang Y S, Ma E, et al. Microstructures and upconversion luminescence of Er3+doped and Er3+/Yb3+co-doped oxyfluoride glass ceramics [J]. Mat. Chem. and Phys.,2007,101 (1):234-237.
[48]Maciel G S, Biswas A, Prasad P N. Infrared-to-visible Eu3+energy upconversion due to cooperative energy transfer from an Yb3+ion pair in a sol-gel processed multi-component silica glass [J]. Opt Commun,2000,178:65.
[49]Zheng H R, Wang X J, Qu S X, et al. Dynamical processes of Ln3+ions doped in LaF3 nanocrystals embedded in transparent oxyfluoride glass [J]. J. Lumin.,2006, 119:153.
[50]Silva J E C, de Sa G F, Santa-Cruz P A, Red, green and blue light generation in fluoride glasses controlled by double excitation [J]. J. Alloys Compd.,2001, 323-324:336-339.
[51]Fujiwara H, Sasaki K, Upconversion lasing of a thulium-ion-doped fluorozirconate glass microsphere [J]. J. Appl. Phys.,1999,86(5):2385-2388.
[52]Qiu J., Kawamoto Y, J. Highly efficient blue up-conversion of Tm3+in Nd3+-Yb3+-Tm3+co-doped ZrF4-based fluoride glass [J]. J. Fluorine Chem.,2001, 110(2):175-180.
[53]Qiu J, Kawamoto Y. Blue up-conversion luminescence and energy transfer process in Nd3+-Yb3+-Tm3+co-doped ZrF4-based glasses [J]. J. Appl. Phys.,2002, 91:954.
[54]Ye C C, Hewak D W, Hempstead M, et al. Spectral properties of Er3+-doped gallium lanthanum sulphide glass [J]. J. Non-Cryst. Solids,1996,208:56.
[55]陈宝玖,王海宇,秦伟平等.高效的红外到可见上转换氟氧化物玻璃材料[J].光谱学与光谱分析仪器,2000,20(3)：257-260.
[56]Stantos P V, Gouveia E A, Araujo M T, et al. IR-visible upconversion and thermal effects in Pr3+/Yb3+codoped Ga2O3:La2S3 chalcogenide glasses [J]. J. Phys.:Condens. Matter.,2000,12:10003.
[57]Wang X J, Xie Y, Guo Q X. Synthesis of high quality inorganic fullerene-like BN hollow spheres via a simple chemical route [J]. Chem. Commun.,2003,21: 2688-2689.
[58]Jiang X C, Yan C H, Sun L D, et al. Hydrothermal homogeneous urea precipitation of hexagonal YBO3:Eu3+nanocrystals with improved luminescent properties [J]. J. Solid State Chem.,2003,175:245.
[59]Yu D, Yam V. Hydrothermal-Induced Assembly of Colloidal Silver Spheres into Various Nanoparticles on the Basis of HTAB-Modified Silver Mirror Reaction [J]. J. Phys. Chem. B,2005,109:5497-5503.
[60]Cao M, Hu. C, Wang B. The first fluoride one-dimensional nanostructures: microemulsion-mediated hydrothermal synthesis of BaF2 whiskers [J]. J. Am. Chem. Soc.,2003,125:11196-11197.
[61]Liu B, Zeng H C. Mesoscale organization of CuO nanoribbons:formation of "dandelions" [J]. J. Am. Chem. Soc.,2004,126:8124-8125.
[62]Sen D, Deb P, Mazumder S, et al. Microstructural investigations of ferrite nanoparticles prepared bynonaqueous precipitation route [J]. Mater. Res. Bull, 2000,35:1243-1250.
[63]Bazzoni M, Bettinelli M, Daldosso M, et al. Structural and thermal investigation of gadolinium gallium mixed oxides obtained by coprecipitation:Observation of a new metastable phase [J]. J Solid State Chem,2005,178:2301-2305.
[64]余朝义.稀土掺杂氟化物上转换发光材料的制备及光谱特性研究[D].吉林：长春理工大学材料物理与化学学院,2006.
[65]Chen H Y, Zhang J H, Wang X J, et al. The effect of the size of raw Gd(OH)3 precipitation on the crystal structure and PL properties of Gd2O3:Eu [J]. J Colloid Interf Sci,2006,297:130-133.
[66]Wang M, Mi C C, Wang S, et al. Synthesis and Characterization of NaYF4:Yb, Er Upconversion Fluorescent Nanoparticles via a Co-Precipitation Method [J]. Spectrosc Spect Anal,2009,29:3327-3331.
[67]N. Bloembergen, Solid State Infrared Quantum Counters [J]. Phys. Rev. Lett., 1959,2:84.
[68]Johnson L F, Guggenheim H J, Infrared-pumped visible laser [J]. Appl. Phys. Lett.,1971,19(2):44-46.
[69]Joubert M F, Photon avalanche upconversion in rare earth laser materials [J]. Opt. Mat.,1999,11(2-3):181-203.
[70]Antipenko B M, Dumbravyanu R V, Perlin Yu E, et al. Spectroscopic aspects of the BaYb2F8 laser medium [J]. Opt. Spectrosc.,1985,59(3):377-380.
[71]McFarlane R A, Upconversion laser in BaYb2F8:Er5% pumped by ground-state and excited-state absorption [J]. J. Opt. Soc. Am. B.,1994,11(5):871-870.
[72]J. Y. Allain, M. Monerie, and H. Poignant, [J]. Electron. Lett.,26 (1990):166.
[73]Piehler D. Upconversion process creates compact blue/green lasers [J]. Laser Focus World,1993,Nov:95.
[74]J. Zhang, W. Qin, J. Zhang, et al. Self-Assembly of Yb3+-Tm3+Co-Doped YF3 Elongated Nanocrystals into Nanobundles of Straw and Up-Conversion Fluorescence [J]. J. Nanosci. Nanotechnol.,2008,8:1388.
[75]Y. Wang, W. Qin, J. Zhang, et al. Bright Green Upconversion Fluorescence of Yb3+, Er3+-codoped Fluoride Colloidal Nanocrystal and Submicrocrystal Solutions [J]. Chem. Lett.,2007,36:912.
[76]J. W. Stouwdam and F. C. J. M. van Veggel. Near-infrared Emission of Redispersible Er3+, Nd3+, and Ho3+Doped LaF3 Nanoparticles [J]. Nano Lett., 2002,2:733.
[77]Kramer K W, Biner D, Frei G, et al. Hexagonal Sodium Yttrium Fluoride Based Green and Blue Emitting Upconversion Phosphors [J]. Chem. Mater.,2004,16: 1244-1251.
[78]Osiac E, Heumann, Huber G, et al, Orange and red upconversion laser pumped by an avalanche mechanism in Pr3+, Yb3+:BaY2F8 [J]. Appl. Phys. Lett.,2003,82: 3832.
[79]Zellmer H, Riedel P, Tunnermann A, Visible upconversion lasers in praseodymium-ytterbium-doped fibers [J]. Appl. Phys. Lett,1999,69:417.
[80]Xie P, Gosnell T R, Room-temperature upconversion fiber laser tunable in the red, orange, green, and blue spectral regions [J]. Opt. Lett.,1995,20:1014.
[81]Wang G F, Qin W P, Enhancement of violet and ultraviolet upconversion emissions in Yb3+/Er3+-codoped YF3 nanocrystals [J]. Optical Materials,2008, 31:296.
[82]Chen G Y, Somesfalean G, Zhang Z G, et al. Ultraviolet upconversion fluorescence in rare-earth-ion-doped Y2O3 induced by infrared diode laser excitation [J]. Opt. Lett.,2007,32:87-89.
[83]Cao C Y, Qin W P, Enhanced Ultraviolet Up-conversion Emissions of Tm3+/Yb3+ codoped YF3 Nanocrystals [J]. J. Fluorine Chem.,2008,129:204-209.
[84]Qin G S, Qin W P, Intense ultraviolet upconversion luminescence from Yb3+and Tm3+codoped amorphous fluoride particles synthesized by pulsed laser ablation [J]. Opt. Commun.,2004,242:215.
[85]Chen X B, and Song Z F, Study on six-photon and five-photon ultraviolet upconversion luminescence [J]. J. Opt. Soc. Am. B,2007,24:965-971.
[86]L. Diaz-Torres, E. De la Rosa-Cruz, P. Salas, et al. Concentration enhanced red upconversion in nanocrystalline ZrO2:Er [J]. J. Phys. D:Appl. Phys.,2004,37: 489-2495.
[87]S. Ivanova, F. Pelle, A. Tkachuk, et al. Upconversion luminescence dynamics of Er-doped fluoride crystals for optical converters [J]. J. Lumin,2008,128: 914-917.
[88]S. Ivanova, and F. Pelle, Strong 1.53 μm to NIR-VIS-UV upconversion in Er-doped fluoride glass for high-efficiency solar cells [J]. J. Opt. Soc. Am. B, 2009,26:1930-1938.
[89]X. Chen, Study of up-conversion luminescence of Er (2):ZBLAN excited by 1520 nm laser [J]. Opt. commun.,2004,242:565-573.
[90]G. Qin, W. Qin, C. Wu, et al. Enhancement of ultraviolet upconversion in Yb and Tm codoped amorphous fluoride film prepared by pulsed laser deposition [J]. J. Appl. Phys.,2003,93:4328.
[91]Chen X B, Wang Y F, and Song Z F, Multiphoton ultraviolet and visible upconversion luminescence of Tm3+-Yb3+co-doped oxyfluoride glass [J]. Opt. Commun.,2007,227:335-341.
[92]G. Wang, W. Qin, L. Wang, et al. Intense ultraviolet upconversion luminescence from hexagonal NaYF4:Yb3+/Tm3+microcrystals [J]. Opt. Express,2008,16: 11907-11914.
[93]W. Qin, C. Cao, L. Wang, et al. Ultraviolet upconversion fluorescence from°DJ of Gd3+induced by 980 nm excitation [J]. Opt. Lett.,2008,33:2167-2169.
[94]Gharavi A R, and McPherson G L, Ultraviolet emissions from Gd3+ions excited by energy transfer from pairs of photoexcited Er3+ions:upconversion luminescence fromCsMgCl3 crystals doped with Gd3+and Er3+[J]. J, Opt. Soc. Am. B,1994,11:913-918.
[95]Cao C Y, Qin W P, Zhang J S, et al. Ultraviolet upconversion emissions of Gd3+ [J]. Opt. Lett.,2008,33:857.
[96]Wang L L, Xue X J, Shi F, et al. Ultraviolet and violet upconversion fluorescence of europium (Ⅲ)doped YF3 nanocrystals [J]. Opt. Lett.,2009,34:2781-2783.
[97]Wang L L, Xue X J, Chen H, et al. Unusual radiative transitions of Eu3+ions in Yb/Er/Eu tri-doped NaYF4 nanocrystals under infrared excitation [J]. Chem. Phys. Lett.,2010,485:183-186.
[98]Chen G, Liang H, Liu H, et al. Near vacuum ultraviolet luminescence of Gd3+and Er3+ions generated by super saturation upconversion processes [J]. Opt. Express, 2009,17:16366-16371.
[99]Wegh R T, Donker H, Oskam K D, et al. Visible quantum cutting in Eu3+-doped gadolinium fluorides via downconversion [J]. J. Lumin.,1999,82:93-104.
[100]Wegh R T, Donker H, Oskam K D, et al. Visible quantum cutting in LiGdF4: Eu3+through downconversion [J]. Science,1999,283:663-665.
[101]Zhang Q Y, Yang C H, Jiang Z H, et al. Concentration-dependent near-infrared quantum cutting in GdBO3:Tb3+,Yb3+nanophosphors [J]. Appl. Phys. Lett.,2007, 90:061914-061916.
[102]Feofilov S P, Zhou Y, Jeong J Y, et al. Sensitization of Gd3+and the dynamics of quantum splitting in GdF3:Pr,Eu [J]. J. Lumin.,2007,122-123:503-505.
[103]G. S. Yi and G. M. Chow. Colloidal LaF3:Yb, Er, LaF3:Yb, Ho and LaF3:Yb, Tm nanocrystals with multicolor upconversion fluorescence [J]. J. Mater. Chem., 2005,15:4460.
[104]Sivakumar S, Boyer J C, Bovero E, et al. Up-conversion of 980 nm light into white light from sol-gel derived thin film made with new combinations of LaF3:Ln3+nanoparticles [J]. J. Mater. Chem.,2009,19:2392.
[105]Wang F, Liu X G, Upconversion multicolor fine-tuning:visible to near-infrared emission from lanthanide-doped NaYF nanoparticles [J]. J. Am. Chem. Soc., 2008,130(17):5642-5643.
[106]Sivakumar S, Van Veggel F C J M, Raudsepp M, Bright white light through up-conversion of a single NIR source from sol-gel derived thin film made with Ln3+doped LaF3 nanoparticles [J]. J. Am. Chem. Soc.,2005,127 (36): 12464-12465.
[107]L. Wang, and Y. Li. Na(Yi.5Nao.5)F6 Single-Crystal Nanorods as Multicolor Luminescent Materials [J]. Nano Lett.,2006,6:1645-1649.
[108]Fan Zhang, Ying Wan, Ting Yu, et al. Uniform Nanostructured Arrays of Sodium Rare-Earth Fluorides for Highly Efficient Multicolor Upconversion Luminescence [J]. Angew. Chem. Int. Ed.,2007,46:7976-7979.
[109]Lim S F, Riehn R, Ryu W S, et al. In vivo and scanning electron microscopy imaging of upconverting nanophosphors in Caenorhabditis elegans [J]. Nano Lett.,2006,6:169.
[110]Chatterjee D K, Rufaihah a J, Zhang Y. Upconversion fluorescence imaging of cells and small animals using lanthanide doped nanocrystals [J]. Biomaterials, 2008,29:937.
[111]Gibart P, Auzel F, Guillaume J, and Zahraman K, Below band-gap IR response ofsubstrate-free GaAs solar cells using two-photon up-conversion [J]. Japanese journal of applied physics,1996,35(1):4401-4402.
[112]T Trupke, M A Green, and P Wurfel, Improving solar cell effciencies by uo-conversion of sub-band-gap light [J]. J. Appl. Phys.,2002,92(7):43-47.
[113]Shalav A, Richards B S, Trupke T, et al. Application of NaYF4:Er3+ up-converting phosphors for enhanced near-infrared silicon solar cell response [J]. Appl. Phys. Lett.,2005,86:013505.
[114]Liang X F, Huang X Y, and Zhang Q Y, Gd2(MoO4)3:ErJ+nanophosphors for an enhancement of silicon solar-cell near-infrared response [J]. J. Fluorescence, 2009,19(2)：285-289.
[115]张思远,毕宪章.稀土光谱理论, [M].北京：吉林科学技术出版社,1991.
[116]徐叙瑢,苏勉曾.发光学与发光材料, [M].北京：化工工业出版社,2004.
[117]黄世华,激光光谱学原理和方法,[M].长春：吉林大学出版社,2001.
[118]李湘宁,工程光学,[M].北京：科学出版社,2005.
[119]Pollack, D. Chang, and N. Moise, Upconversion-pumped infrared erbium laser [J]. J. Appl. Phys.,1986,60:4077.
[120]A. Silversmith, W. Lenth, and R. Macfarlane, Green infrared-pumped erbium upconversion laser [J]. Appl. Phys. Lett.,1987,51:1977.
[121]S. Georgescu, and O. Toma, Modeling of a green upconversion pumped Er: YAG laser [J]. SPIE 2004,5581:245.
[122]F Vetrone, J Boyer, J Capobianco, et al. Significance of Yb concentration on the upconversion mechanisms in codoped Y2O3:Er3+, Yb3+nanocrystals [J]. J. Appl. Phys.,2004,96:661.
[123]H. Song, B. Sun, T. Wang, et al. Three-photon upconversion luminescence phenomenon for the green levels in Er3+/Yb3+codoped cubic nanocrystalline yttria [J]. Solid State Commun,2004,132:409-413.
[124]J F Suyver, A Aebischer, S Garcia-Revilla, et al. Anomalous power dependence of sensitized upconversion luminescence [J]. Phys. Rev. B,2005,71:125123.
[125]X. Bai, H. Song, G. Pan, et al. Size-Dependent Upconversion Luminescence in Er3+/Yb3+-Codoped Nanocrystalline Yttria:Saturation and Thermal Effects [J]. J. Phys. Chem. C,2007,111:13611-13617.
[126]X. Qu, H. Song, X. Bai, et al. Preparation and Upconversion Luminescence of Three-Dimensionally Ordered Macroporous ZrO2:Er3+, Yb3+[J]. Inorg. Chem., 2008,47:9654-9659.
[127]W T Carnall, P R Fields, and K Rajnak, Electronic Energy Levels in the Trivalent Lanthanide Aquo Ions. I. Pr, Nd, Pm, Sm, Dy, Ho, Er, and Tm [J]. J. Chem. Phys.,1968,49:4424-4442.
[128]Zheng K Z, Wang L L, Zhang D S, et al. Power switched multiphoton upconversion emissions of Er3+in Yb3+/Er3+codoped β-NaYF4 microcrystals induced by 980 nm excitation [J]. Opt. Express,2010,18:2934-2939.
[129]Sytsma J, Imbush G F, and Blasse G, The decay of the 6I7/2 term level of Gd3+in YOCI and LiYF4 [J]. J. Phys. Condens. Matter,1990,2:5171-5178.
[130]Noginov M A, Curley M, Venkateswarlu P, et al. Excitation scheme for the upper energy levels in a Tm:Yb:BaY2Fg laser crystal [J]. J. Opt. Soc. Am. B, 1997,14 (8):2126-2136.
[131]L Aarts, B M van der Ende, and A. Meijerink, Downconversion for solar cells in NaYF4:Er, Yb [J]. J. Appl. Phys.,2009,106:023522.
[132]Zheng K Z, Zhao D, Zhang D S, et al. Temperature-dependent six-photon upconversion fluorescence of Er3+[J]. J. Fluorine Chem.,2011,132:5-8.
[133]Zheng K Z, Qin W P, Wang G F, et. al. Upconversion Luminescence Properties of Yb3+, Gd3+, and Tm3+Co-Doped NaYF4 Microcrystals Synthesized by the Hydrothermal Method. [J]. J. Nanosci. Nanotechnol.,2010,10:1920-1923.
[134]Zheng K Z, Zhao D, Zhang D S, et al. Ultraviolet upconversion fluorescence of Er3+induced by 1560 nm laser excitation [J]. Opt. Lett,2010,35:2442-2444.
[135]A Steckl, J Heikenfeld, and S Allen, Light wave coupled flat panel displays and solid-state lighting using hybrid inorganic/organic materials [J]. Journal of Display Technology,2005,1:157.
[136]D Chen, Y Wang, K Zheng, et al. Bright upconversion white light emission in transparent glass ceramic embedding Tm+/Er+/Yb+:β-YF3 nanocrystals [J]. Appl. Phys. Lett.,2007,91:51903.
[137]J. DiMaio, B. Kokuoz, and J. Ballato, White light emissions through down-conversion of rare-earth doped LaF3 nanoparticles [J]. Opt. Express,2006, 14:11412-11417.
[138]X Liu, C Lin, and J Lin, White-Light Emission from Eu3+in CaIn2O4 Host Lattices [J]. Appl. Phys. Lett.,2007,90:081904-081906.
[139]G Chen, Y Liu, Y Zhang, et al. Bright white upconversion luminescence in rare-earth-ion-doped Y2O3 nanocrystals [J]. Appl. Phys. Lett.,2007,91:133103.
[140]C. Cao, W. Qin, J. Zhang, et al. Up-conversion white light of Tm3+/Er3+/Yb3+ tri-doped CaF2 phosphors [J]. Optics Communications,2008,281:1716-1719.
[141]D Matsuura, Red, green, and blue upconversion luminescence of trivalent-rare-earth ion-doped Y2O3 nanocrystals [J]. Appl. Phys. Lett.,2002,81: 4526.
[142]H. Guo, N. Dong, M. Yin, et al. Visible upconversion in rare earth ion-doped Gd2O3 nanocrystals [J]. J. Phys. Chem. B,2004,108:19205-19209.
[143]Schietinger S, Menezes L D, Lauritzen B, et al. Observation of Size Dependence in Multicolor Upconversion in Single Yb3+, Er3+Codoped NaYF4 Nanocrystals [J]. Nano Lett.,2009,9:2477.
[144]Naruke H, Mori T, Yamase T. Luminescence properties and excitation process of a near-infrared to visible up-conversion color-tunable phosphor [J]. Opt. Mater.,2009,31:1483.
[145]V Mahalingam, F Mangiarini, F Vetrone, et al. Bright White Upconversion Emission from Tm3+/Yb3+/Er3+-Doped Lu3Ga5O12 Nanocrystals [J]. J. Phys. Chem. C,2008,112:17745-17749.
[146]J. Yang, C. Zhang, C. Peng, et al. Controllable Red, Green, Blue (RGB) and Bright White Upconversion Luminescence of Lu2O3:Yb3+/Er3+/Tm3+ Nanocrystals through Single Laser Excitation at 980 nm [J]. Chemistry-A European Journal,2009,15:4649-4655.
[147]A Gouveia-Neto, L Bueno, R Do Nascimento, et al. White light generation by frequency upconversion in Tm/Ho/Yb-codoped fluorolead germanate glass [J]. Appl. Phys. Lett.,2007,91:091114.
[148]H Amorim, M Vermelho, A Gouveia-Neto, et al. Red-green-blue upconversion emission and energy-transfer between Tm3+and Er3+ions in tellurite glasses excited at 1.064μm [J]. J. Solid State Chem.,2003,171:278-281.
[149]J da Silva, G De Sa, and P Santa-Cruz, White light simulation by up-conversion in fluoride glass host [J]. J. Alloys Compd.,2002,344:260-263.
[150]G. Jia, K. Liu, Y. Zheng, et al. Highly Uniform Gd(OH)3 and Gd2O3:Eu3+ Nanotubes:Facile Synthesis and Luminescence Properties [J]. J. Phys. Chem. C, 2009,113(15):6050-6055.
[151]C. Chang, F. Kimura, T. Kimura, et al. Preparation and characterization of rod-like Eu:Gd2O3 phosphor through a hydrothermal routine [J]. Materials letters, 2005,59:1037-1041.
[152]C. Chang, Q. Zhang, and D. Mao, The hydrothermal preparation, crystal structure and photoluminescent properties of GdOOH nanorods [J]. Nanotechnology,2006,17:1981-1985.
[153]A Patra, C Friend, R Kapoor, et al. Upconversion in Er3+:ZrO2 nanocrystals [J]. J. Phys. Chem. B,2002,106:1909-1912.
[154]G. Chen, Y. Zhang, G. Somesfalean, et al. Two-color upconversion in rare-earth-ion-doped ZrO nanocrystals [J]. Appl. Phys. Lett.,2006,89:163105.
[155]G Glaspell, J Anderson, J Wilkins, et al. Vapor Phase Synthesis of Upconverting Y2O3 Nanocrystals Doped with Yb3+, Er3+, Ho3+, and Tm3+to Generate Red, Green, Blue, and White Light [J]. J. Phys. Chem. C,2008,112:11527-11531.
[156]B. Dong, H. Song, H. Yu, et al. Upconversion Properties of Ln3+Doped NaYF4/Polymer Composite Fibers Prepared by Electrospinning [J]. J. Phys. Chem. C,2008,112(5):1435-1440.
[2]J. Y. Allain, M. Monerie, and H. Poignant. Tunable green upconversion erbium fiber laser [J]. Electron. Lett.,1992,28:111
[3]Heine F, Heumann E, Danget T, et al. Green upconversion continuous wave Er3+ LiYF4 laser at room temperature [J]. Appl. Phys. Lett.,1994,65(4):383-385.
[4]El-Agmy R M. Upconversion CW laser at 284 nm in a Nd:YAG-pumped double-cladding thulium-doped ZBLAN fiber laser [J]. Laser Phys.,2008,18: 803.
[5]Zhao Y, Fleming S. All-solid state and all-fiber blue upconversion laser [J]. Electron. Lett.,1996,32:1199-1200.
[6]Liu X M, Jia P Y, Lin J, et al. Monodisperse spherical core-shell structured SiO2-CaTiO3:Pr3+phosphors for field emission displays [J]. J. Appl. Phys.,2006, 99(12):124902-124902(7).
[7]Milliez J, Rapaport A, Bass M, et al. High-Brightness White-Light Source Based on Up-Conversion Phosphors [J]. J. Display Technol.2006,2(3):307-311.
[8]Downing E, Hesselink L, Ralston J, et al. A three-color, solid-state, three-dimensional display [J]. Science,1996,273:1185-1189.
[9]Yang Z M, Feng Z M, and Jiang Z H. Upconversion emission in multi-doped glasses for full colour display [J]. J Phys D Appl Phys,2005,38:1629-1632.
[10]Maciel G S, Biswas A, Kapoor R, et al. Blue cooperative upconversion in Yb3+-doped multicomponent sol-gel-processed silica glass for three-dimensional display [J]. Appl. Phys. Lett.,2000,76:1978-1980.
[11]Jiang S, Zhang Y, Lim K M, et al. NIR-to-visible upconversion nanoparticles for fluorescent labeling and targeted delivery of siRNA [J]. Nanotechnology 2009, 20:155101.
[12]Xiong L Q, Chen Z G, Tian Q W, et al. High Contrast Upconversion Luminescence Targeted Imaging in Vivo Using Peptide-Labeled Nanophosphors [J]. Anal Chem.,2009,81:8687-8694.
[13]Wang C, Cheng L A, and Liu Z A. Drug delivery with upconversion nanoparticles for multi-functional targeted cancer cell imaging and therapy [J]. Biomaterials,2011,32:1110-1120.
[14]Kamimura M, Miyamoto D, Saito Y, et al. Design of poly(ethylene glycol)/streptavidin coimmobilized upconversion nanophosphors and their application to fluorescence biolabeling [J]. Langmuir,2008,24:8864-8870.
[15]Wang M, Mi C C, Wang W X, et al. Immunolabeling and NIR-Excited Fluorescent Imaging of HeLa Cells by Using NaYF4:Yb, Er Upconversion Nanoparticles [J]. Acs Nano,2009,3:1580-1586.
[16]Ahrens B, Loper P, Goldschmidt J C, et al. Neodymium-doped fluorochlorozirconate glasses as an upconversion model system for high efficiency solar cells [J]. Phys Status Solidi A,2008,205:2822-2830.
[17]B S Richards, Avi Shalav. Enhancing the Near-infrared Spectral Response of Silicon Optoelectronic Devices via Up-conversion [J]. IEEE transaction on electron devices,2007,54:2679-2684.
[18]Ivanova S, Pelle F. Strong 1.53μm to NIR-VIS-UV upconversion in Er-doped fluoride glass for high-efficiency solar cells [J]. J Opt Soc Am B,2009,26: 1930-1938.
[19]A Shalav, B S Richards, and M A Green.d, Luminescent layers for enhanced silicon solar cell performance:Up-conversion [J]. Sol Energ Mat Sol C,2007,91: 829-842.
[20]de Wild J, Meijerink A, Rath J K, et al. Towards upconversion for amorphous silicon solar cells [J]. Sol Energ Mat Sol C,2010,94:1919-1922.
[21]Qin W P, Zhang D S, Zhao D, et al. Near-infrared Photocatalysis Based on YF3:Yb3+,Tm3+/TiO2 Core/shell Nanoparticles [J]. Chem. Commun,2010,46: 2304-2306.
[22]戎红仁,王平,顾浩.新型的防伪材料红外上转换材料[J].印刷杂志,2002,8：190-191.
[23]刘政威,佘仲明.能量上转换功能材料及其制作的防伪标记材料：中国,ZL00113404.3[P],2004.
[24]Auzel F, Comt. Rend, computeur quantique par transfer d'energie de Yb3+, Tm3+ dans an tungstate mixte et dans un VeiTe gemanate [J]. C. R. Acad. Sci. (Paris), 1966,263B:819-821.
[25]Auzel F, Upconversion and Anti-Stokes Processes with f and d Ions in Solids [J]. Chem. Rev.,2004,104:139.
[26]Pollnau M, Gamelin D R, Luthi S R, et al. Power dependence of upconversion luminescence in lanthanide and transition-metal-ion systems [J]. Phys. Rev. B, 2000,61:3337.
[27]Yang F Z, Yi G S, Chen D P, et al. Synthesis and up-conversion luminescence properties of nanocrystal Yb, Ho co-doped sodium yttrium fluoride [J]. Chem. J. Chinese. U.,2004,25:1589.
[28]Chen G, Liu H, Somesfalean G, et al. Upconversion emission tuning from green to red in Yb3+/Ho3+-codoped NaYF4 nanocrystals by tridoping with Ce3+ions [J]. Nanotechnology,2009,20:385704.
[29]Goh S C, Pattie R, Byrne C, et al. Blue and red laser action in Nd3+and Pr3+ co-doped fluorozirconate glass [J]. Appl. Phys. Lett.,1995,67(6):768-770.
[30]Zhang X, Serrano C, Daran E, et al. Infrared-laser-induced upconversion from Nd3+:LaF3 heteroepitaxial layers on CaF2(111) substrates by molecular beam epitaxy [J]. Phys. Rev. B,2000,62:4446-4454.
[31]Wada N, Kojim K. Dispersion and upconversion fluorescence of Nd3+ions in zinc chloride-based glasses [J]. J Am Ceram Soc,2002,85:590-594.
[32]Wang Y H, Junichi O, New transparent vitroceramics codoped with Er3+and Yb3+for efficient frequency upconversion [J]. Appl. Phys. Lett.,1993,63: 3268-3270.
[33]Man S O, Pun E Y B, Chung P S, Upconversion luminescence of Er3+in alkali bismuth gallate glasses [J]. Appl. Phys. Lett.,2000,77 (4):483-485.
[34]Song F, Su J, Tan H, et al. The energy transfer processes between the Er3+and Tm3+in Er, Tm-codoped-NaY(WO4)2 crystal [J]. Opt. Commun.,2004,241(4-6): 455-463.
[35]Jouart J P, Oomen E W J, Upconversion in Er3+-Doped Fluorite-Type Crystals Excited at 800 nm [J]. Phys. Stat. Sol. (b),1992,172 (1):461-470.
[36]Balda R, Garcia-Adeva A J, Voda M, et al. Upconversion processes in Er3+-doped KPb2Cl5 [J]. Phys. Rev. B,2004,69 (20):205203-205210.
[37]Hehlen M P, Kuditcher A, Lenef A L, et al. Nonradiative dynamics of avalanche upconversion in Tm:LiYF4 [J]. Phys. Rev. B,2000,61(2):1116-1128.
[38]Chen D Q, Wang Y S, Yu Y L, et al. Intense ultraviolet upconversion luminescence from Tm3+/Yb3+:YF3 nanocrystals embedded glass ceramic [J]. Appl. Phys. Lett.,2007,91:051920-051922.
[39]Martin I R, Mendez-Ramos J, Rodriguez V D, et al. Increase of the 800 nm excited Tm3+blue upconversion emission in fluoroindate glasses by codoping with Yb3+ions [J]. Opt. Mater.,2003,22 (4):327-333.
[40]Huang L H, Liu X R, Xu W, et al. Infrared and visible luminescence properties of Er3+and Yb3+ions codoped Ca3Al2Ge3O12 glass under 978 nm diode laser excitation [J]. J. Appl. Phys.,2001,90 (11):5550-5553.
[41]Qin G S, Qin W P, Huang S H, et al. Infrared-to-violet upconversion from Yb3+ and Er3+codoped amorphous fluoride film prepared by pulsed laser deposition [J]. J. Appl. Phys.,2002,92 (11):6936-6938.
[42]Y. Mita, K. Hirama, N. Ando, et al. Luminescence processes in Tm3+-and Er3+-ion-activated, Yb3+-ion-sensitized infrared upconversion devices [J]. J. Appl. Phys.,1993,74:4703.
[43]Thrash R J, Johnson L F, Upconversion laser emission from YbJ+-sensitized TmJ+ in BaY2F8[J]. J. Opt. Soc.Am. B.,1994,11(5):881-885.
[44]Higuchi H, Takahashi M, Kawamoto Y, et al. Optical transitions and frequency upconversion emission of Er3+ions in Ga2S3--GeS2--La2S3 glasses [J]. J. Appl. Phys.,1998,83:19.
[45]Dwivedi Y, Thakur S N, Rai S B. Study of frequency upconversion in Yb3+/Eu3+ by cooperative energy transfer in oxyfluoroborate glass matrix [J]. Appl. Phys. B-Lasers O.,2007,89:45.
[46]Huang L, Yamashita T, Jose R, et al. Intense ultraviolet emission from Tb3+and Yb3+codoped glass ceramic containing CaF2 nanocrystals [J]. Appl. Phys. Lett., 2007,90:131116.
[47]Hu Z J, Wang Y S, Ma E, et al. Microstructures and upconversion luminescence of Er3+doped and Er3+/Yb3+co-doped oxyfluoride glass ceramics [J]. Mat. Chem. and Phys.,2007,101 (1):234-237.
[48]Maciel G S, Biswas A, Prasad P N. Infrared-to-visible Eu3+energy upconversion due to cooperative energy transfer from an Yb3+ion pair in a sol-gel processed multi-component silica glass [J]. Opt Commun,2000,178:65.
[49]Zheng H R, Wang X J, Qu S X, et al. Dynamical processes of Ln3+ions doped in LaF3 nanocrystals embedded in transparent oxyfluoride glass [J]. J. Lumin.,2006, 119:153.
[50]Silva J E C, de Sa G F, Santa-Cruz P A, Red, green and blue light generation in fluoride glasses controlled by double excitation [J]. J. Alloys Compd.,2001, 323-324:336-339.
[51]Fujiwara H, Sasaki K, Upconversion lasing of a thulium-ion-doped fluorozirconate glass microsphere [J]. J. Appl. Phys.,1999,86(5):2385-2388.
[52]Qiu J., Kawamoto Y, J. Highly efficient blue up-conversion of Tm3+in Nd3+-Yb3+-Tm3+co-doped ZrF4-based fluoride glass [J]. J. Fluorine Chem.,2001, 110(2):175-180.
[53]Qiu J, Kawamoto Y. Blue up-conversion luminescence and energy transfer process in Nd3+-Yb3+-Tm3+co-doped ZrF4-based glasses [J]. J. Appl. Phys.,2002, 91:954.
[54]Ye C C, Hewak D W, Hempstead M, et al. Spectral properties of Er3+-doped gallium lanthanum sulphide glass [J]. J. Non-Cryst. Solids,1996,208:56.
[55]陈宝玖,王海宇,秦伟平等.高效的红外到可见上转换氟氧化物玻璃材料[J].光谱学与光谱分析仪器,2000,20(3)：257-260.
[56]Stantos P V, Gouveia E A, Araujo M T, et al. IR-visible upconversion and thermal effects in Pr3+/Yb3+codoped Ga2O3:La2S3 chalcogenide glasses [J]. J. Phys.:Condens. Matter.,2000,12:10003.
[57]Wang X J, Xie Y, Guo Q X. Synthesis of high quality inorganic fullerene-like BN hollow spheres via a simple chemical route [J]. Chem. Commun.,2003,21: 2688-2689.
[58]Jiang X C, Yan C H, Sun L D, et al. Hydrothermal homogeneous urea precipitation of hexagonal YBO3:Eu3+nanocrystals with improved luminescent properties [J]. J. Solid State Chem.,2003,175:245.
[59]Yu D, Yam V. Hydrothermal-Induced Assembly of Colloidal Silver Spheres into Various Nanoparticles on the Basis of HTAB-Modified Silver Mirror Reaction [J]. J. Phys. Chem. B,2005,109:5497-5503.
[60]Cao M, Hu. C, Wang B. The first fluoride one-dimensional nanostructures: microemulsion-mediated hydrothermal synthesis of BaF2 whiskers [J]. J. Am. Chem. Soc.,2003,125:11196-11197.
[61]Liu B, Zeng H C. Mesoscale organization of CuO nanoribbons:formation of "dandelions" [J]. J. Am. Chem. Soc.,2004,126:8124-8125.
[62]Sen D, Deb P, Mazumder S, et al. Microstructural investigations of ferrite nanoparticles prepared bynonaqueous precipitation route [J]. Mater. Res. Bull, 2000,35:1243-1250.
[63]Bazzoni M, Bettinelli M, Daldosso M, et al. Structural and thermal investigation of gadolinium gallium mixed oxides obtained by coprecipitation:Observation of a new metastable phase [J]. J Solid State Chem,2005,178:2301-2305.
[64]余朝义.稀土掺杂氟化物上转换发光材料的制备及光谱特性研究[D].吉林：长春理工大学材料物理与化学学院,2006.
[65]Chen H Y, Zhang J H, Wang X J, et al. The effect of the size of raw Gd(OH)3 precipitation on the crystal structure and PL properties of Gd2O3:Eu [J]. J Colloid Interf Sci,2006,297:130-133.
[66]Wang M, Mi C C, Wang S, et al. Synthesis and Characterization of NaYF4:Yb, Er Upconversion Fluorescent Nanoparticles via a Co-Precipitation Method [J]. Spectrosc Spect Anal,2009,29:3327-3331.
[67]N. Bloembergen, Solid State Infrared Quantum Counters [J]. Phys. Rev. Lett., 1959,2:84.
[68]Johnson L F, Guggenheim H J, Infrared-pumped visible laser [J]. Appl. Phys. Lett.,1971,19(2):44-46.
[69]Joubert M F, Photon avalanche upconversion in rare earth laser materials [J]. Opt. Mat.,1999,11(2-3):181-203.
[70]Antipenko B M, Dumbravyanu R V, Perlin Yu E, et al. Spectroscopic aspects of the BaYb2F8 laser medium [J]. Opt. Spectrosc.,1985,59(3):377-380.
[71]McFarlane R A, Upconversion laser in BaYb2F8:Er5% pumped by ground-state and excited-state absorption [J]. J. Opt. Soc. Am. B.,1994,11(5):871-870.
[72]J. Y. Allain, M. Monerie, and H. Poignant, [J]. Electron. Lett.,26 (1990):166.
[73]Piehler D. Upconversion process creates compact blue/green lasers [J]. Laser Focus World,1993,Nov:95.
[74]J. Zhang, W. Qin, J. Zhang, et al. Self-Assembly of Yb3+-Tm3+Co-Doped YF3 Elongated Nanocrystals into Nanobundles of Straw and Up-Conversion Fluorescence [J]. J. Nanosci. Nanotechnol.,2008,8:1388.
[75]Y. Wang, W. Qin, J. Zhang, et al. Bright Green Upconversion Fluorescence of Yb3+, Er3+-codoped Fluoride Colloidal Nanocrystal and Submicrocrystal Solutions [J]. Chem. Lett.,2007,36:912.
[76]J. W. Stouwdam and F. C. J. M. van Veggel. Near-infrared Emission of Redispersible Er3+, Nd3+, and Ho3+Doped LaF3 Nanoparticles [J]. Nano Lett., 2002,2:733.
[77]Kramer K W, Biner D, Frei G, et al. Hexagonal Sodium Yttrium Fluoride Based Green and Blue Emitting Upconversion Phosphors [J]. Chem. Mater.,2004,16: 1244-1251.
[78]Osiac E, Heumann, Huber G, et al, Orange and red upconversion laser pumped by an avalanche mechanism in Pr3+, Yb3+:BaY2F8 [J]. Appl. Phys. Lett.,2003,82: 3832.
[79]Zellmer H, Riedel P, Tunnermann A, Visible upconversion lasers in praseodymium-ytterbium-doped fibers [J]. Appl. Phys. Lett,1999,69:417.
[80]Xie P, Gosnell T R, Room-temperature upconversion fiber laser tunable in the red, orange, green, and blue spectral regions [J]. Opt. Lett.,1995,20:1014.
[81]Wang G F, Qin W P, Enhancement of violet and ultraviolet upconversion emissions in Yb3+/Er3+-codoped YF3 nanocrystals [J]. Optical Materials,2008, 31:296.
[82]Chen G Y, Somesfalean G, Zhang Z G, et al. Ultraviolet upconversion fluorescence in rare-earth-ion-doped Y2O3 induced by infrared diode laser excitation [J]. Opt. Lett.,2007,32:87-89.
[83]Cao C Y, Qin W P, Enhanced Ultraviolet Up-conversion Emissions of Tm3+/Yb3+ codoped YF3 Nanocrystals [J]. J. Fluorine Chem.,2008,129:204-209.
[84]Qin G S, Qin W P, Intense ultraviolet upconversion luminescence from Yb3+and Tm3+codoped amorphous fluoride particles synthesized by pulsed laser ablation [J]. Opt. Commun.,2004,242:215.
[85]Chen X B, and Song Z F, Study on six-photon and five-photon ultraviolet upconversion luminescence [J]. J. Opt. Soc. Am. B,2007,24:965-971.
[86]L. Diaz-Torres, E. De la Rosa-Cruz, P. Salas, et al. Concentration enhanced red upconversion in nanocrystalline ZrO2:Er [J]. J. Phys. D:Appl. Phys.,2004,37: 489-2495.
[87]S. Ivanova, F. Pelle, A. Tkachuk, et al. Upconversion luminescence dynamics of Er-doped fluoride crystals for optical converters [J]. J. Lumin,2008,128: 914-917.
[88]S. Ivanova, and F. Pelle, Strong 1.53 μm to NIR-VIS-UV upconversion in Er-doped fluoride glass for high-efficiency solar cells [J]. J. Opt. Soc. Am. B, 2009,26:1930-1938.
[89]X. Chen, Study of up-conversion luminescence of Er (2):ZBLAN excited by 1520 nm laser [J]. Opt. commun.,2004,242:565-573.
[90]G. Qin, W. Qin, C. Wu, et al. Enhancement of ultraviolet upconversion in Yb and Tm codoped amorphous fluoride film prepared by pulsed laser deposition [J]. J. Appl. Phys.,2003,93:4328.
[91]Chen X B, Wang Y F, and Song Z F, Multiphoton ultraviolet and visible upconversion luminescence of Tm3+-Yb3+co-doped oxyfluoride glass [J]. Opt. Commun.,2007,227:335-341.
[92]G. Wang, W. Qin, L. Wang, et al. Intense ultraviolet upconversion luminescence from hexagonal NaYF4:Yb3+/Tm3+microcrystals [J]. Opt. Express,2008,16: 11907-11914.
[93]W. Qin, C. Cao, L. Wang, et al. Ultraviolet upconversion fluorescence from°DJ of Gd3+induced by 980 nm excitation [J]. Opt. Lett.,2008,33:2167-2169.
[94]Gharavi A R, and McPherson G L, Ultraviolet emissions from Gd3+ions excited by energy transfer from pairs of photoexcited Er3+ions:upconversion luminescence fromCsMgCl3 crystals doped with Gd3+and Er3+[J]. J, Opt. Soc. Am. B,1994,11:913-918.
[95]Cao C Y, Qin W P, Zhang J S, et al. Ultraviolet upconversion emissions of Gd3+ [J]. Opt. Lett.,2008,33:857.
[96]Wang L L, Xue X J, Shi F, et al. Ultraviolet and violet upconversion fluorescence of europium (Ⅲ)doped YF3 nanocrystals [J]. Opt. Lett.,2009,34:2781-2783.
[97]Wang L L, Xue X J, Chen H, et al. Unusual radiative transitions of Eu3+ions in Yb/Er/Eu tri-doped NaYF4 nanocrystals under infrared excitation [J]. Chem. Phys. Lett.,2010,485:183-186.
[98]Chen G, Liang H, Liu H, et al. Near vacuum ultraviolet luminescence of Gd3+and Er3+ions generated by super saturation upconversion processes [J]. Opt. Express, 2009,17:16366-16371.
[99]Wegh R T, Donker H, Oskam K D, et al. Visible quantum cutting in Eu3+-doped gadolinium fluorides via downconversion [J]. J. Lumin.,1999,82:93-104.
[100]Wegh R T, Donker H, Oskam K D, et al. Visible quantum cutting in LiGdF4: Eu3+through downconversion [J]. Science,1999,283:663-665.
[101]Zhang Q Y, Yang C H, Jiang Z H, et al. Concentration-dependent near-infrared quantum cutting in GdBO3:Tb3+,Yb3+nanophosphors [J]. Appl. Phys. Lett.,2007, 90:061914-061916.
[102]Feofilov S P, Zhou Y, Jeong J Y, et al. Sensitization of Gd3+and the dynamics of quantum splitting in GdF3:Pr,Eu [J]. J. Lumin.,2007,122-123:503-505.
[103]G. S. Yi and G. M. Chow. Colloidal LaF3:Yb, Er, LaF3:Yb, Ho and LaF3:Yb, Tm nanocrystals with multicolor upconversion fluorescence [J]. J. Mater. Chem., 2005,15:4460.
[104]Sivakumar S, Boyer J C, Bovero E, et al. Up-conversion of 980 nm light into white light from sol-gel derived thin film made with new combinations of LaF3:Ln3+nanoparticles [J]. J. Mater. Chem.,2009,19:2392.
[105]Wang F, Liu X G, Upconversion multicolor fine-tuning:visible to near-infrared emission from lanthanide-doped NaYF nanoparticles [J]. J. Am. Chem. Soc., 2008,130(17):5642-5643.
[106]Sivakumar S, Van Veggel F C J M, Raudsepp M, Bright white light through up-conversion of a single NIR source from sol-gel derived thin film made with Ln3+doped LaF3 nanoparticles [J]. J. Am. Chem. Soc.,2005,127 (36): 12464-12465.
[107]L. Wang, and Y. Li. Na(Yi.5Nao.5)F6 Single-Crystal Nanorods as Multicolor Luminescent Materials [J]. Nano Lett.,2006,6:1645-1649.
[108]Fan Zhang, Ying Wan, Ting Yu, et al. Uniform Nanostructured Arrays of Sodium Rare-Earth Fluorides for Highly Efficient Multicolor Upconversion Luminescence [J]. Angew. Chem. Int. Ed.,2007,46:7976-7979.
[109]Lim S F, Riehn R, Ryu W S, et al. In vivo and scanning electron microscopy imaging of upconverting nanophosphors in Caenorhabditis elegans [J]. Nano Lett.,2006,6:169.
[110]Chatterjee D K, Rufaihah a J, Zhang Y. Upconversion fluorescence imaging of cells and small animals using lanthanide doped nanocrystals [J]. Biomaterials, 2008,29:937.
[111]Gibart P, Auzel F, Guillaume J, and Zahraman K, Below band-gap IR response ofsubstrate-free GaAs solar cells using two-photon up-conversion [J]. Japanese journal of applied physics,1996,35(1):4401-4402.
[112]T Trupke, M A Green, and P Wurfel, Improving solar cell effciencies by uo-conversion of sub-band-gap light [J]. J. Appl. Phys.,2002,92(7):43-47.
[113]Shalav A, Richards B S, Trupke T, et al. Application of NaYF4:Er3+ up-converting phosphors for enhanced near-infrared silicon solar cell response [J]. Appl. Phys. Lett.,2005,86:013505.
[114]Liang X F, Huang X Y, and Zhang Q Y, Gd2(MoO4)3:ErJ+nanophosphors for an enhancement of silicon solar-cell near-infrared response [J]. J. Fluorescence, 2009,19(2)：285-289.
[115]张思远,毕宪章.稀土光谱理论, [M].北京：吉林科学技术出版社,1991.
[116]徐叙瑢,苏勉曾.发光学与发光材料, [M].北京：化工工业出版社,2004.
[117]黄世华,激光光谱学原理和方法,[M].长春：吉林大学出版社,2001.
[118]李湘宁,工程光学,[M].北京：科学出版社,2005.
[119]Pollack, D. Chang, and N. Moise, Upconversion-pumped infrared erbium laser [J]. J. Appl. Phys.,1986,60:4077.
[120]A. Silversmith, W. Lenth, and R. Macfarlane, Green infrared-pumped erbium upconversion laser [J]. Appl. Phys. Lett.,1987,51:1977.
[121]S. Georgescu, and O. Toma, Modeling of a green upconversion pumped Er: YAG laser [J]. SPIE 2004,5581:245.
[122]F Vetrone, J Boyer, J Capobianco, et al. Significance of Yb concentration on the upconversion mechanisms in codoped Y2O3:Er3+, Yb3+nanocrystals [J]. J. Appl. Phys.,2004,96:661.
[123]H. Song, B. Sun, T. Wang, et al. Three-photon upconversion luminescence phenomenon for the green levels in Er3+/Yb3+codoped cubic nanocrystalline yttria [J]. Solid State Commun,2004,132:409-413.
[124]J F Suyver, A Aebischer, S Garcia-Revilla, et al. Anomalous power dependence of sensitized upconversion luminescence [J]. Phys. Rev. B,2005,71:125123.
[125]X. Bai, H. Song, G. Pan, et al. Size-Dependent Upconversion Luminescence in Er3+/Yb3+-Codoped Nanocrystalline Yttria:Saturation and Thermal Effects [J]. J. Phys. Chem. C,2007,111:13611-13617.
[126]X. Qu, H. Song, X. Bai, et al. Preparation and Upconversion Luminescence of Three-Dimensionally Ordered Macroporous ZrO2:Er3+, Yb3+[J]. Inorg. Chem., 2008,47:9654-9659.
[127]W T Carnall, P R Fields, and K Rajnak, Electronic Energy Levels in the Trivalent Lanthanide Aquo Ions. I. Pr, Nd, Pm, Sm, Dy, Ho, Er, and Tm [J]. J. Chem. Phys.,1968,49:4424-4442.
[128]Zheng K Z, Wang L L, Zhang D S, et al. Power switched multiphoton upconversion emissions of Er3+in Yb3+/Er3+codoped β-NaYF4 microcrystals induced by 980 nm excitation [J]. Opt. Express,2010,18:2934-2939.
[129]Sytsma J, Imbush G F, and Blasse G, The decay of the 6I7/2 term level of Gd3+in YOCI and LiYF4 [J]. J. Phys. Condens. Matter,1990,2:5171-5178.
[130]Noginov M A, Curley M, Venkateswarlu P, et al. Excitation scheme for the upper energy levels in a Tm:Yb:BaY2Fg laser crystal [J]. J. Opt. Soc. Am. B, 1997,14 (8):2126-2136.
[131]L Aarts, B M van der Ende, and A. Meijerink, Downconversion for solar cells in NaYF4:Er, Yb [J]. J. Appl. Phys.,2009,106:023522.
[132]Zheng K Z, Zhao D, Zhang D S, et al. Temperature-dependent six-photon upconversion fluorescence of Er3+[J]. J. Fluorine Chem.,2011,132:5-8.
[133]Zheng K Z, Qin W P, Wang G F, et. al. Upconversion Luminescence Properties of Yb3+, Gd3+, and Tm3+Co-Doped NaYF4 Microcrystals Synthesized by the Hydrothermal Method. [J]. J. Nanosci. Nanotechnol.,2010,10:1920-1923.
[134]Zheng K Z, Zhao D, Zhang D S, et al. Ultraviolet upconversion fluorescence of Er3+induced by 1560 nm laser excitation [J]. Opt. Lett,2010,35:2442-2444.
[135]A Steckl, J Heikenfeld, and S Allen, Light wave coupled flat panel displays and solid-state lighting using hybrid inorganic/organic materials [J]. Journal of Display Technology,2005,1:157.
[136]D Chen, Y Wang, K Zheng, et al. Bright upconversion white light emission in transparent glass ceramic embedding Tm+/Er+/Yb+:β-YF3 nanocrystals [J]. Appl. Phys. Lett.,2007,91:51903.
[137]J. DiMaio, B. Kokuoz, and J. Ballato, White light emissions through down-conversion of rare-earth doped LaF3 nanoparticles [J]. Opt. Express,2006, 14:11412-11417.
[138]X Liu, C Lin, and J Lin, White-Light Emission from Eu3+in CaIn2O4 Host Lattices [J]. Appl. Phys. Lett.,2007,90:081904-081906.
[139]G Chen, Y Liu, Y Zhang, et al. Bright white upconversion luminescence in rare-earth-ion-doped Y2O3 nanocrystals [J]. Appl. Phys. Lett.,2007,91:133103.
[140]C. Cao, W. Qin, J. Zhang, et al. Up-conversion white light of Tm3+/Er3+/Yb3+ tri-doped CaF2 phosphors [J]. Optics Communications,2008,281:1716-1719.
[141]D Matsuura, Red, green, and blue upconversion luminescence of trivalent-rare-earth ion-doped Y2O3 nanocrystals [J]. Appl. Phys. Lett.,2002,81: 4526.
[142]H. Guo, N. Dong, M. Yin, et al. Visible upconversion in rare earth ion-doped Gd2O3 nanocrystals [J]. J. Phys. Chem. B,2004,108:19205-19209.
[143]Schietinger S, Menezes L D, Lauritzen B, et al. Observation of Size Dependence in Multicolor Upconversion in Single Yb3+, Er3+Codoped NaYF4 Nanocrystals [J]. Nano Lett.,2009,9:2477.
[144]Naruke H, Mori T, Yamase T. Luminescence properties and excitation process of a near-infrared to visible up-conversion color-tunable phosphor [J]. Opt. Mater.,2009,31:1483.
[145]V Mahalingam, F Mangiarini, F Vetrone, et al. Bright White Upconversion Emission from Tm3+/Yb3+/Er3+-Doped Lu3Ga5O12 Nanocrystals [J]. J. Phys. Chem. C,2008,112:17745-17749.
[146]J. Yang, C. Zhang, C. Peng, et al. Controllable Red, Green, Blue (RGB) and Bright White Upconversion Luminescence of Lu2O3:Yb3+/Er3+/Tm3+ Nanocrystals through Single Laser Excitation at 980 nm [J]. Chemistry-A European Journal,2009,15:4649-4655.
[147]A Gouveia-Neto, L Bueno, R Do Nascimento, et al. White light generation by frequency upconversion in Tm/Ho/Yb-codoped fluorolead germanate glass [J]. Appl. Phys. Lett.,2007,91:091114.
[148]H Amorim, M Vermelho, A Gouveia-Neto, et al. Red-green-blue upconversion emission and energy-transfer between Tm3+and Er3+ions in tellurite glasses excited at 1.064μm [J]. J. Solid State Chem.,2003,171:278-281.
[149]J da Silva, G De Sa, and P Santa-Cruz, White light simulation by up-conversion in fluoride glass host [J]. J. Alloys Compd.,2002,344:260-263.
[150]G. Jia, K. Liu, Y. Zheng, et al. Highly Uniform Gd(OH)3 and Gd2O3:Eu3+ Nanotubes:Facile Synthesis and Luminescence Properties [J]. J. Phys. Chem. C, 2009,113(15):6050-6055.
[151]C. Chang, F. Kimura, T. Kimura, et al. Preparation and characterization of rod-like Eu:Gd2O3 phosphor through a hydrothermal routine [J]. Materials letters, 2005,59:1037-1041.
[152]C. Chang, Q. Zhang, and D. Mao, The hydrothermal preparation, crystal structure and photoluminescent properties of GdOOH nanorods [J]. Nanotechnology,2006,17:1981-1985.
[153]A Patra, C Friend, R Kapoor, et al. Upconversion in Er3+:ZrO2 nanocrystals [J]. J. Phys. Chem. B,2002,106:1909-1912.
[154]G. Chen, Y. Zhang, G. Somesfalean, et al. Two-color upconversion in rare-earth-ion-doped ZrO nanocrystals [J]. Appl. Phys. Lett.,2006,89:163105.
[155]G Glaspell, J Anderson, J Wilkins, et al. Vapor Phase Synthesis of Upconverting Y2O3 Nanocrystals Doped with Yb3+, Er3+, Ho3+, and Tm3+to Generate Red, Green, Blue, and White Light [J]. J. Phys. Chem. C,2008,112:11527-11531.
[156]B. Dong, H. Song, H. Yu, et al. Upconversion Properties of Ln3+Doped NaYF4/Polymer Composite Fibers Prepared by Electrospinning [J]. J. Phys. Chem. C,2008,112(5):1435-1440.