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1.
13.9nm软X射线激光用大面积多层膜分束镜研制   总被引:3,自引:3,他引:0       下载免费PDF全文
 基于分束镜反射率和透射率的乘积为衡量标准的原则,设计了13.9nm软X射线激光干涉测量所需的多层膜分束镜,用磁控溅射法在有效面积达10mm×10mm,厚100nm的氮化硅窗口上镀制Mo/Si多层膜,实现了分束镜制作。用表面轮廓仪实测分束镜面形精度达到nm量级,同步辐射反射率计测试表明,分束镜的反射率和透射率乘积约4%。  相似文献
2.
X射线天文望远镜的进展   总被引:3,自引:0,他引:3  
综述了近年来X射线天文望远镜(如准直型望远镜、编码孔径望远镜、正入射周期多层膜望远镜、掠入射单层膜望远镜和掠入射非周期多层膜望远镜以及新型的“龙虾眼”型望远镜)的发展;阐述了各种X射线天文望远镜工作的原理和成像特点,指出各种X射线天文望远镜之间的性能是相互补充的;简要说明了国内近年来在X射线天文望远镜研究方面取得的进展,并展望了下一步工作.  相似文献
3.
Investigation of ultra-short-period W/C multilayers for soft X-ray optics   总被引:2,自引:0,他引:2  
The periodic multilayer has many interesting and useful mechanical, electrical, magnetic, and optical properties, which are related to either the coherent effect of mod- ulation or the structure of thin films. The periodic multilayer mirrors are used for enhancing reflectivity in the wavelength range of 0.1—10 nm from grazing to normal incidence. Therefore, the multilayer reflectors have been used successfully in a range of applications, including extreme ultraviolet (EUV) lithography[1], so…  相似文献
4.
13.9 nm马赫贞德干涉仪用软X射线分束镜研究   总被引:2,自引:2,他引:0       下载免费PDF全文
 介绍了13.9 nm马赫贞德干涉仪用软X射线分束镜的设计、制备与性能检测。基于分束镜反射率和透过率乘积最大的评价标准,设计了13.9 nm软X射线激光干涉实验用多层膜分束镜。采用磁控溅射方法在有效面积为10 mm×10 mm、厚度为100 nm的Si3N4基底上镀制了Mo/Si多层膜,制成了多层膜分束镜。利用X射线掠入射衍射的方法测量了Mo/Si多层膜的周期。用扩束He-Ne激光束进行的投影成像方法定性分析了分束镜的面形精度,利用光学轮廓仪完成了分束镜面形精确测量。利用北京同步辐射装置测量了分束镜反射率和透射率,在13.9 nm处,分束镜反射率和透过率乘积达4%。使用多层膜分束镜构建了软X射线马赫贞德干涉仪,并应用于13.9 nm软X射线激光干涉实验中,获得了清晰的含有C8H8等离子体电子密度信息的动态干涉条纹。  相似文献
5.
Local bifurcation analysis of a four-dimensional hyperchaotic system   总被引:2,自引:0,他引:2  
Local bifurcation phenomena in a four-dlmensional continuous hyperchaotic system, which has rich and complex dynamical behaviours, are analysed. The local bifurcations of the system are investigated by utilizing the bifurcation theory and the centre manifold theorem, and thus the conditions of the existence of pitchfork bifurcation and Hopf bifurcation are derived in detail. Numerical simulations are presented to verify the theoretical analysis, and they show some interesting dynamics, including stable periodic orbits emerging from the new fixed points generated by pitchfork bifurcation, coexistence of a stable limit cycle and a chaotic attractor, as well as chaos within quite a wide parameter region.  相似文献
6.
An effectual method is presented to determine the profiles of a tungsten (W) layer, such as the density, the thickness and the roughness in the multilayer structures, using the x-ray reflectivity technique. To avoid oxidation effects of tungsten, a B4 C capping layer is deposited onto to the W layer. To observe the profiles of the tungsten layer with different thicknesses, three groups of W/B4 C bilayers with different thicknesses are prepared by using ultra high vacuum dc magnetron sputtering and measured by an x-ray diffractometer. A type of genetic algorithm called the differential evolution is used to simulate the measurement data so as to obtain the parameters of bilayers. According to the simulation, it is shown that the W layer density varies from 95.26% to 97.51% compared to the bulk. In our experiment, the deposition rate is 0.044 nm/s, and the thickness is varied in the range of 9.8-19.4 nm.  相似文献
7.
Ni films are deposited by using ultra high vacuum dc magnetron sputtering onto silicon substrates at room temperature, and the high-quality and high-density films are prepared. The parameters, such as thickness, density and surface roughness, are obtained by using small-angle x-ray diffraction (XRD) analyses with the Marquardt gradient-expansion algorithm. The deposition rate is calculated and the Ni single layer can be fabricated precisely. Based on the fitting results, we can find that the surface roughness of the Ni films is about 0.7nm, the densities of Ni films are around 97% and the deposition rate is 0.26nm/s. The roughness of the surface is also characterized by using an atomic force microscope (AFM). The changing trend of the surface roughness in the simulation of XRD is in good agreement with the AFM measurement.  相似文献
8.
Recently, with the development of hard X-ray telescopes[1-3] and the third generation synchrotron sources[4], hard X-ray focus optics have been applied widely. For such applications, the reflective mirrors with relatively broad angular range for hard X-ray radiation such as Cu Kα line (λ = 0.154 nm), are required to extend the view field and flux of optics, where bent crystal and single layer metal mirrors cannot be used be- cause of too small grazing incident angle. The periodic multilaye…  相似文献
9.
磁控溅射材料沉积速率的定标方法的研究   总被引:1,自引:0,他引:1  
介绍了一种利用磁控溅射制备多层膜速率的定标方法。用高精度磁控溅射镀膜设备在同一块基片上先后镀制了两种周期的多层膜,用X射线衍射仪对其进行掠入射衍射测量,测量数据经线性拟合,可同时求得两种多层膜的周期,进而得到镀膜速率。与常用的定标方法相比,该方法不仅可以得到与常用定标方法相同的实验结果,而且提高了工作效率。  相似文献
10.
水窗波段反射式偏振光学元件的设计和制作   总被引:1,自引:0,他引:1  
水窗波段是软X射线进行生物活细胞显微成像的最佳波段,因此对于水窗波段偏振光学元件的研究有着非常重要的意义。用菲涅耳公式计算出在水窗波段内不同材料组合对应不同波长的最大反射率,模拟分析了多层膜周期和表界面粗糙度对多层膜偏振光学元件性能的影响。用超高真空磁控溅射镀膜设备,制作出2.40nm、3.00nm和4.30nm波长处W/B4C多层膜偏振元件,并用X射线衍射仪对元件的周期厚度进行了测量,得到的测量结果与设计值偏差很小,可以进行实际应用。为水窗波段反射式偏振光学元件的研究提供了理论依据,同时也为相应偏振光学元件的制备确定了合适的工艺参量。  相似文献
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