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991.
Bi‐Qi Zhang Song‐Bo Li Qing Xiao Ju Li Jian‐Jun Sun 《Journal of Raman spectroscopy : JRS》2013,44(8):1120-1125
The recently reported shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS) is considered as the next generation of advanced spectroscopy for its surface and molecular generality. With the aim to utilize the virtues of shell‐isolated strategy and advance the SHINERS technique, we introduce a silane‐based rapid synthesis method of silica‐coating Au nanorods (Au@SiO2 NRs) with manoeuvrable ultra‐thin shell and tunable SPR. The results demonstrate that the SPR of Au NRs could be optimized to obtain large Raman enhancement using either 633 nm or 785 nm laser. Differing from previously reported Au@SiO2 NRs synthesis method, we can tune the silica shell thickness within several nanometers to maximize the Raman signal while effectively eliminating the exterior interference. And this advanced synthesis method has also significantly reduced the silica‐coating time from one day to ca. 1 h. This method as a new development of SHINERS technique has successfully got enhanced signal in solution Raman tests of malachite green, giving a great potential to be extended to in‐situ measurement for daily life detection. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
992.
采用溶胶-凝胶法在Pt/Ti/SiO2/Si衬底上制备了不同La掺杂浓度PLZT(x/40/60)薄膜- x射线衍射分析表明制备的PLZT(x/40/60)薄膜是具有单一钙钛矿结构的多晶薄膜- 通过红外椭圆偏振光谱仪测量了波长为2-5—12-6μm范围内PLZT薄膜的椭偏光谱,采用经典色 散模型拟合获得PLZT薄膜的红外光学常数,同时也拟合获得PLZT薄膜的厚度- 随着La掺杂浓 度的增大,折射率逐渐减小- 而消光系数除PLZT(4/40/60)薄膜外,呈现逐渐增大的趋势- 分析表明这些差异主要与PLZ
关键词:
PLZT薄膜
红外光学性质
红外椭圆偏振光谱 相似文献
993.
对不同温度下沉积的ZnS薄膜的结晶情况和光学特性进行了研究, 结果表明:沉积温度对ZnS薄膜的物理和光学特性有较大影响, 不同的温度沉积的ZnS薄膜具有不同的择优取向, 牢固度也大不相同; 不同沉积温度下, ZnS薄膜的光学常数也不尽相同. 温度为115 ℃和155 ℃时, ZnS薄膜的物理性能和光学性能较差, 不适合空间用光学薄膜的研制使用. 而190 ℃和230 ℃沉积温度下所得薄膜具有较好的物理和光学性能, 适合于不同要求的空间用薄膜器件的研制使用.
关键词:
硫化锌薄膜
沉积温度
表面形貌
光学常数 相似文献
994.
《Current Applied Physics》2014,14(5):744-748
Raman scattering spectroscopy has been performed on high quality Co-doped ZnO epitaxial films, which were grown on Al2O3 (0001) by oxygen-plasma assisted molecular beam epitaxy. Raman measurements revealed two local vibration modes (LVMs) at 723 and 699 cm−1 due to the substitution of Co2+ in wurtzite ZnO lattice. The LVM at 723 cm−1 is found to be an elemental sensitive vibration mode for Co substitution. The LVM at 699 cm−1 can be attributed to enrichment of Co2+ bound with oxygen vacancy, the cobalt–oxygen vacancy–cobalt complexes, in Zn1−xCoxO films associated with ferromagnetism. The intensity of LVM at 699 cm−1, as well as saturated magnetization, enhanced after the vacuum annealing and depressed after oxygen annealing. 相似文献
995.
Vanadium oxide thin films were prepared by sol-gel method, then subjected to Nd:YAG laser (CW, 1064 nm) radiation. The characteristics of the films were changed by varying the intensity of the laser radiation. The nanocrystalline films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). XRD revealed that above 102 W/cm2 the original xerogel structure disappears and above 129 W/cm2 the films become totally polycrystalline with an orthorhombic structure. From TEM observations, we can see that due to laser radiation, the originally fibrillar-like particles disappear and irregular shaped, layer structured V2O5 particles are created. From XPS spectra we can conclude that due to laser radiation the O/V ratio increased with higher intensities. 相似文献
996.
一种提高薄板稳定分析精度的方法 总被引:1,自引:0,他引:1
在薄板稳定分析中,九参数三角形薄板单元因其形状简单,使用方便,在实际工程中得到了广泛应用。本文基于参数调正的几何刚度矩阵,对九参数三角形薄板单元的一致刚度矩阵进行了修正,为提高计算精度提供了一种有效方法。 相似文献
997.
Different thin fluorocarbon (FC) films were deposited on Si(111) using plasma polymerisation and then exposed to X-ray radiation. Changes in the chemical composition of the deposited fluorocarbon films as a function of irradiation time were investigated in situ using X-ray photoelectron spectroscopy. The evaluation of the C1s and F1s core level induced emission as a function of exposure to X-ray radiation (Mg Kα, hν = 1253.6 eV) reveals changes in the surface chemical composition of the FC polymer structure. The presented results indicate a high defluorination under X-ray irradiation. Additionally, binding energy shifts of the F1s and C1s peaks during the exposure associated with surface charging effects were observed. With ongoing exposure the surface charging decreases continuously and the FC surfaces become more conductive due to changes in the polymer structure. Different models have been used to describe the decomposition kinetics and surface composition. 相似文献
998.
Modern condensed-matter physics is increasingly concerned with the design, synthesis, analysis, and exploitation of chemically complex materials and structures. Complex metal oxides and strongly correlated electron systems such as YBa2Cu3O7−x and La1−xSrxMnO3 are paradigmatic examples. Their production in the form of high-quality thin films is of both technological and fundamental importance and has stimulated a concerted effort in the last two decades to find and optimize efficient techniques to this end. This review discusses the physics behind and the requirements for synthesizing high-quality films of such materials and examines fundamental aspects of the growth processes associated with magnetron sputtering and pulsed laser deposition, the two techniques which presently offer the best solutions in this burgeoning field. 相似文献
999.
Thi Bang Tam Dao Kim Ngoc Pham Yi-Lung Cheng Sang Sub Kim Bach Thang Phan 《Current Applied Physics》2014,14(12):1707-1712
The as-deposited WO3 thin films were post-annealed at different temperatures (300 °C and 600 °C) in air to investigate a correlation between crystallinity and switching behavior of WO3 thin films. Associating the results of XRD, FTIR, XPS and FESEM measurements, the annealing-caused crystallinity change contributes to the variation of the switching behaviors of the WO3 thin films. The as-deposited WO3 films with low crystalline structure are preferred for random Ag conducting path, resulting in large switching ratio but fluctuating I–V hysteresis, whereas the annealed WO3 films with crystallized compact structure limits Ag conducting path, favoring the stable I–V hysteresis but small switching ratio. It is therefore concluded that electrochemical redox reaction-controlled resistance switching depends not only on electrode materials (inert and reactive electrodes) but also on crystallinity of host oxide. 相似文献
1000.