共查询到20条相似文献,搜索用时 15 毫秒
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We have measured the third-order nonlinear susceptibilities χ(3) of SnO2 nanoparticles both naked and coated with a layer of stearic acid by using Z-scan technique with 1.06μm pulse from a Q-switched Nd:YAG laser. The results show that the χ(3) of these nanoparticles is much larger than that of the bulk material. Moreover, we find that two-photon absorption is not present for the naked nanoparticles but it is preseut for the coated ones, and the χ(3) of the latter is larger than that of the former. It is demonstrated that the surface situations of the nanoparticles have great influence on their nonlinear optical properties. 相似文献
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采用双靶反应溅射制得SnO2:Zr薄膜,并对它作了150°C下SO2气敏光学特性试验,首次发现在适当工艺条件下制得的SnO2:Zr薄膜在近红外波段(1.7~3μm)对SO2气体具有明显的光学气敏特性,在2.65μm附近透过率上升幅度达10%左右.Zr的引入增强了SnO2薄膜对SO2的吸附能力.用二次离子质谱对吸附SO2前后的薄膜作了组分相对含量分析.本实验结果对今后研究高性能SO2气敏传感器有一定的价值. 相似文献
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SECOND-ORDER NONLINEAR OPTICAL PROPERTIES OF TITANIUM DIOXIDE NANOPARTICLES AND NANOPARTICLES-DYE COMPOSITES 下载免费PDF全文
Hyper-Rayleigh Scattering (HRS) technique was used to study the second-order nonlinear optical (NLO) responses of aqueous titanium dioxide (TiO2) nanoparticles of 10nm in size, and two nanoparticles-dye composites prepared by adding rhodamine B (Rh610) or the organic tosylate salt of dimethylaminostilbazolium (DAST). Results showed that the "per particle" first hyperpolarizability β for TiO2 nanoparticles is very large, in the range of 1026 esu. With adding Rh610 and DAST, the HRS signals of the composites were further enhanced. And in TiO2/Rh610 composite the enhancement was obviously greater than that of TiO2/DAST composite. It has proved that non-centrosymmetry of the nanocrystal/solution interface contributes mainly to its large "per particle" β, overwhelming the nanocrystal core. So the interactions between nanoparticles surfaces and adsorbed dyes were very important for their second-order NLO responses. HRS technique provides a useful new NLO method to characterize the surface structures and microenvironment of nanoscale materials. 相似文献
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金属包裹纳米微粒的光学特性研究(英文) 总被引:2,自引:0,他引:2
金属包裹纳米粒子是一种纳米量级的介质球核外包裹薄金属层的纳米粒子.在本文中,Au包裹Au2S纳米粒子被抽象成微型电磁谐振腔,其谐振波长决定于Au2S介质球核的半径.运用经典电磁理论可以得到谐振波长和谐振能量.由于Au包层很薄(2nm),这种微型谐振腔的耦合方式是有别于传统方式的透射耦合,因此Au包层的厚度决定了谐振的能量以及谐振腔品质因子Q.此外,本文还讨论了吸收峰的线宽. 相似文献
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采用超细过滤方法,分别制备含有平均线度小于2nm的超细SnO2纳米晶粒的酸性和碱性溶胶溶液.通过动态光散射、X射线衍射和晶粒透射电子显微镜像测量,确定了SnO2晶粒的线度.对其光吸收谱测量发现,超细过滤后酸性和碱性溶胶溶液中晶粒的带边光吸收能量均有明显蓝移.分析结果表明,SnO2晶粒的线度减小是同类晶粒带边光吸收蓝移的主要原因.
关键词:
超细纳米晶粒
透射电子显微镜
带边光吸收
表面化学修饰 相似文献
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We have synthesized core/shell structure ZnO composite nanoparticles by surface chemical modification. This new composite material shows a large optical gap redshift compared with the homogeneous ZnO nanoparticles. The visible photoluminescence ranging from blue to red in color with fast decay time may be as signed to the interfacial bound-exciton-like emission. 相似文献
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Amorphous TiO2 thin films and ZnFe2O4 doped TiO2 composite films were deposited by radio frequency magnetron sputtering. The effect of ZnFe2O4 doping on the optical properties of TiO2 thin films was reported. Our results show that the absorption edge of TiO2 thin films and composite films exhibits a blue shift with decreasing annealing temperature. The absorption edge of composite films has moved to visible spectrum range, and a very large red shift occurs in comparison with TiO2 thin film. An enhanced photoluminescence in ZnFe2O4 doped anatase TiO2 thin film at room temperature. 相似文献
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应用射频磁控共溅射方法在石英玻璃和抛光硅片上制备了InP/SiO2复合薄膜,并在几种条件下对这些薄膜进行退火.X射线光电子能谱和卢瑟福背散射实验结果表明,复合薄膜中InP和SiO2的化学组分都大体上符合化学计量配比.X射线衍射和激光喇曼谱实验结果都证实了复合薄膜中形成了InP纳米晶粒.磷气氛保护下的高温(520℃)退火可以消除复合薄膜中残存的In和In2O3并得到了纯InP/SiO2纳米复合薄膜.实验观察到了室温下纳米复合薄膜的明显的光学吸收边蓝移现象和光学非线性的极大增强
关键词:
InP
纳米晶粒
微观结构
光学性质 相似文献
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