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81.
82.
Cu doped Bi,Al:DyIG and Bi,Ga:DyIG thin films have been prepared on glass substrates by sol-gel method. As-deposited films were amorphous, and after annealing polycrystalline magnetic thin films could be obtained. X-ray diffraction pattern showed that the films were garnet phase with no preferred crystal orientation. The H
c
value of 7 kOe was obtained in Cu doped Bi, Al:DyIG films, and the Faraday rotation angle was about 7°/µm at the wavelength of 500 nm. An extremely high H
c
value of 13 kOe at room temperature has been got in Bi, Ga:DyIG films, and the Faraday rotation angle was 8°/µm at the wavelength of 510 nm for the optimum value of Ga content. The perpendicular magnetic anisotropy (Ku) of garnet films on glass substrate resulted from the inverse magnetostriction. The influence of doping and garnet composition on magnetostriction has been studied. The mechanism of increasing coercive force by Cu doping could be attributed to Cu entering lattice sites. 相似文献
83.
Transition metal (TM) ions have been used as colouring agents in the glass industry for a long time. Recently, great attention has been paid to the TM ion doped glasses for the development of new lasers or luminescence materials. The absorption spectra of TM ions in different kinds of glasses have been studied extensively, but little work has been done for fluorescence and relaxation spectra. In this paper emphasis is laid on analysing the influence of chemical bond characteristics of the base glass on the spectra and the site structure of transition metal ions in glasses. Recent experimental results about the luminescence characteristics of low valence ions (such as Ti3+, Cr3+, V2+, Mn2+, Cu+, Mo3+) in glasses are also reported. 相似文献
84.
Physical properties, such as dielectric loss, acoustic velocity and electrical conductivity of glasses containing several glass-forming oxides were measured at temperatures in the range from −200°C to 200°C. The relationships between the structure and properties of the glasses, and the change in coordination number of individual glass-forming cations in alkali-containing glasses were analysed. It is shown that the glasses containing several glass-forming oxides are characterized by an inhomogeneous structure. 相似文献
85.
JIANG Xiongwei QIU Jianrong ZHU Congshan K.Hirao GAN Fuxi ) Photon Craft Project Shanghai Institute of Optics Fine Mechanics The Chinese Academy of Sciences Shanghai China ) Photon Craft Project ICORP JST Kyoto 《Chinese Journal of Lasers》2001,10(6):422-426
1 Introduction Withthedevelopmentofmultimediaandelectroniccommunicationnetworks,therequirementofdatastorageisincreasingrapidly .Recentyears,intenseresearchactivitiesareundertakingallovertheworldtofindalternatemethodsandrecordingmediatomeettheneedofdat… 相似文献
86.
Sb掺和对TeOx薄膜光学和静态记录特性的影响 总被引:2,自引:2,他引:0
以真空蒸镀法在K9玻璃基底上制备了TeOx:Sb单层薄膜,对薄膜的结构、光学和静态记录特性进行了研究.结果表明,Sb掺和后TeOx薄膜的结构、反射光谱和光学常量均发生了明显变化.TeOx:Sb薄膜具有良好的写入灵敏性并具有了一定的可擦除性能,该类薄膜有望作为可擦除光存储介质. 相似文献
87.
It is known that for the converged laser beam, the axial intensity distribution corresponds to a Gaussian curve, that is, the intensity on the focal plane is the peak intensity. When it defocuses, the intensity would decrease rapidly. In optical data storage, for instance, we expect the intensity within a certain distance to be almost equal. In this paper, we propose to use a pure phase superresolution apodizer to optimize the axial intensity distribution of the converged laser beam and at the same time improve the resolution. The intensity point spread function remains almost identical in a wide range within the focal depth. 相似文献
88.
89.
原子力显微镜对TeOx薄膜中短波长静态记录点结构的分析 总被引:4,自引:0,他引:4
以真空蒸镀法在K9基底上制备了TeOx单层薄膜,采用特定的定位方法,使用原子力显微镜对不同记录功率下薄膜中短滤长静态记录点(514.5nm)的结构进行了分析。实验结果表明薄膜具有良好的记录灵敏性,在记录功率1.5mW时就可产生较高的反射率对比度,记录点具有明显的凹陷和凸起结构,随着记录功率的提高,凹陷和凸起增强,记录点增大。记录点的形态结构和记录前后反射率对比度是直接相关的。研究揭示了原子力显微镜在提高薄膜存储特性如信噪比,存储密度等方面的分析功能。 相似文献
90.
Xiaoyi Li Yiqun Wu Donghong Gu Fuxi Gan 《Journal of Thermal Analysis and Calorimetry》2009,98(2):387-394
Four novel metal(II) complexes, Ni(L)2, Co(L)2, Cu(L)2, and Zn(L)2 (L = 5-(2-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)hydrazono)-1,3-diethyl-2-thioxo-dihydropyrimidine-4,6(1H,5H)-dione), were synthesized using the procedure of diazotization, coupling and metallization. Their structures were identified by elemental analyses, 1H NMR, ESI-MS and FT-IR spectra. The effect of different central metal(II) ions on absorption bands of the metal(II) complexes was researched. The thermal properties of the metal(II) complexes were investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). Furthermore, the thermodynamic parameters, such as activation energy (E*), enthalpy (?H*), entropy (?S*) and free energy of the decomposition (?G*) are calculated from the TG curves applying Coats–Redfern method. The results show that the metal(II) complexes have suitable electronic absorption spectra with blue-violet light absorption at about 350–450 nm, high thermal stability with sharp thermal decomposition thresholds. 相似文献