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Weiming Cheng Sihai Zhao Xiaoming Cheng Xiangshui Miao 《Journal of Superconductivity and Novel Magnetism》2012,25(6):1947-1950
SmCo5 is an emerging perpendicular magnetic material for super-high density magnetic recording, due to its large magnetic anisotropy energy. In this paper, the magnetic moments of SmCo5?x Cu x have been studied using first principles calculation based on density-functional theory (DFT). Calculations are performed using the pseudopotential plane wave DFT code Vienna ab initio simulation package (VASP) with the projector augmented wave (PAW) method. The local density approximation LDA+U method is used for the calculation of the exchange correlation energy of Sm. The calculation results show that the average Co magnetic moment of SmCo5?x Cu x decreases with the increase of Cu doping concentrations, and the influence of the Cu doping on the spin state of Co is greater than that of Sm. The magnetic anisotropy energy of SmCo5 is analyzed. The electronic density of states and the differential in spin densities of atoms show that the spatial distribution of 4f electron and the 4f?C3d coupling are the controlling factors of the magnetic anisotropy energy of SmCo5. 相似文献
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Yajuan Hui Weiming Cheng Gengqi Lin Xiangshui Miao 《Journal of Electronic Materials》2014,43(9):3640-3645
A sputter-deposited strontium ferrite film with perpendicular anisotropy has been developed. The film, composed of La0.33Sr0.67Co0.25Fe11.75O19, has been fabricated directly on quartz glass substrates by radio frequency magnetron sputtering with various heat treatments. The structural and magnetic property dependence of those films on heat treatments has also been studied. The optimized condition is the heat treatment of in situ heating at 400°C and post-annealing at 850°C–900°C. When post-annealing temperature exceeds 900°C, parasitic phases of γ-Fe2O3 and LaFeO3 appear and gradually increase; meanwhile, the magneto plumbite phase gradually decreases. High c-axis perpendicularly oriented films with the coercivity (4148 Oe), remanence squareness ratio (0.89) and perpendicular magnetic anisotropy energy density (1.65 × 106 erg/cm3) are achieved, which is attributed to the single magneto plumbite phase with compact platelet grains and almost complete (0 0 l) texture of the c-axis normal to the film plane. 相似文献
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Jun Xiang Xing Huang Gengqi Lin Jiang Tang Chen Ju Xiangshui Miao 《Journal of Electronic Materials》2014,43(7):2658-2666
Cu(In1?x Ga x )Se2 (CIGS) thin films were deposited by a one-step radio frequency (RF) magnetron sputtering process using a quaternary CIGS target. The influence of substrate temperature on the composition, structure, and optical properties of the CIGS films was investigated. All the CIGS films exhibited the chalcopyrite structure with a preferential orientation along the (112) direction. The CIGS film deposited at 623 K showed significant improvement in film crystallinity and surface morphology compared to films deposited at 523 and 573 K. To simplify the manufacturing procedure of solar cells and avoid the use of the toxic element Cd, the properties of ZnS films prepared by RF sputtering were also investigated. The results revealed that the sputtered ZnS film exhibits good lattice matching with the sputtered CIGS film with significantly lower optical absorption loss. Finally, all-sputtered Cd-free CIGS-based heterojunction solar cells with the structure SLG/Mo/CIGS/ZnS/AZO/Al grids were fabricated without post-selenization. Furthermore, the results demonstrated the feasibility of using a full sputtering process for the fabrication of Cd-free CIGS-based solar cell. 相似文献
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Daoli Zhang Yiping Huang Jianbing Zhang Lin Yuan Xiangshui Miao 《Journal of Electronic Materials》2011,40(4):459-465
ZnO nanopolycrystalline thin films were deposited by the sol–gel technique on glass and silicon, and compared systematically
via atomic force microscopy, scanning electron microscopy, x-ray diffraction, UV–Vis spectrophotometry, and fluorescence spectrophotometry.
The thickness of the ZnO films was measured by ellipsometric microscopy. A higher preheating temperature was needed to obtain
films with a strong preferential orientation. The optimal annealing temperatures for c-axis films on glass and silicon substrates were 525°C and 750°C, respectively. The relative intensity of the blue–green emission
peak tends to increase with the annealing temperature. When the film is annealed in N2, the transmittance of the film reduces while the intensity of the blue–green emission increases. 相似文献
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本文研究了磁光盘介质薄膜-AlN和AlSiN薄膜的电子显微结构,通过透射电镜分析了AlN薄膜的多晶结构和c轴垂直取向;通过X射线衍射分析、透射电镜分析和X射线光电子能谱分析,确定了AlSiN薄膜并不是多晶AlN和SiN薄膜的简单组合,而是形成了稳定的非晶特征结构。且AlSiN薄膜由于其非晶结构而比AlN薄膜的磁光克尔效应增强效果更优越。 相似文献
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Peng Yuan Ge-Qi Mao Yan Cheng Kan-Hao Xue Yunzhe Zheng Yang Yang Pengfei Jiang Yannan Xu Yuan Wang Yuhao Wang Yaxin Ding Yuting Chen Zhiwei Dang Lu Tai Tiancheng Gong Qing Luo Xiangshui Miao Qi Liu 《Nano Research》2022,(4):3667-3674
Hafnia-based ferroelectrics have greatly revived the field of ferroelectric memory(FeRAM),but certain reliability issues must be satisfactorily resolved before ... 相似文献
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相变存储器存储单元瞬态电流测量 总被引:2,自引:0,他引:2
介绍了相变存储单元瞬态电流的测量方法。根据相变存储器的工作特性,利用微弱电流取样电阻测量法,合理选择测量参数测得了相变存储单元的瞬态电流,电阻与电流关系特性曲线和动态电阻。并根据测量电路等效电路模型分析影响测量的因素,估算出电路中的分布电容。 相似文献