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111.
新型X射线靶设计为:由SiO2和TiO2组成具有12个周期的一维光子晶体,在它的中间嵌入光靶材料层作为缺陷层,SiO2,TiO2和光靶层的光学厚度分别为λ4、λ4和λ2,λ为抽运激光波长.与普通平板光靶相比,当抽运光垂直照射到这种光靶时,靶层内部的光强将提高2个数量级,所以抽运激光的阈值强度将降低2个数量级,这有利于X射线激光的小型化.在同样的抽运激光照射下,X射线激光的强度将提高4个数量级,转换效率也将提高约4个数量级.由于平均电离度随抽运激光强度的提高而提高,所以采用这种光靶有利于使X射线激光向短波长推进.
关键词:
X射线激光
光子晶体
光波局域 相似文献
112.
113.
Hyperfine Interactions - The giant magnetoresistance (GMR) effect was an epoch-making discovery in the field of magnetic materials research. In this article, studies on magnetic multilayered... 相似文献
114.
对Sn-C60薄膜进行紫外可见光吸收,X-射线衍射和扫描电镜的测定结果显示,薄膜样品紫外可见光吸收的两个短波段吸收峰比纯C60薄膜的吸收峰显著下降,说明Sn-C60薄膜的电子光吸收跃迁为间接跃迁,能带中有杂质能级的存在;样品的X射线衍射峰则对应于面心立方结构;扫描电镜结果显示薄膜为纳米级颗粒组成。 相似文献
115.
Eremenko L. T. Oreshko G. V. Nesterenko D. A. Lagodzinskaya G. V. Eremenko I. L. 《Russian Chemical Bulletin》2002,51(1):157-159
The reactions of ethylene glycol mononitrate and glycerol 1,3-dinitrate with methylphosphonic dichloride afforded new nitroxyalkyl methylphosphonates. 相似文献
116.
A. Ulyanenkov 《Applied Surface Science》2006,253(1):106-111
Several novel methods for evaluation and interpretation of X-ray data from modern nanostructures are presented along with their applications. The background of methods and their relations to fundamental problems of X-ray analysis is shortly described. The key features of LEPTOS software, which is designed for the analysis of X-ray data measured with various geometries and setups and implements all discussed techniques, are discussed. 相似文献
117.
Catherine Cordier-Robert Thierry Grosdidier Gang Ji Jacques Foct 《Hyperfine Interactions》2006,168(1-3):951-957
Microstructured (atomized) and nanostructured (milled) Fe60Al40 powders together with their corresponding coatings synthesized by High Velocity Oxy-fuel (HVOF) or Atmospheric Plasma Spray (APS) thermal spraying techniques have been characterized by Mössbauer Spectroscopy (MS) and X-ray Diffraction (XRD). The evolution of the microstructure and the atomic ordering degree in the powders and coatings are discussed at the light of the various processing conditions. The operational correlation between the parameters of the duplex morphology of coatings and the processing parameters is discussed. 相似文献
118.
119.
There are many advantages in being able to perform positron annihilation lifetime spectroscopy (PALS) using a variable energy positron beam, the most obvious being the easy identification of different defect types at different depths. The difficulty in conducting variable energy (VE) PALS studies lies in the fact that a “start” signal is required to signal the entry of the positron into the target. Two methods have been used to overcome this problem, namely the bunching technique, which employs radio frequency (RF) cavities and choppers, and secondly the use of secondary electrons emitted from the target. The latter technique is in terms of experimental complexity much simpler, but has in the past suffered from poor time resolution (typically ∼500 ps). In this work, we present a series of computer simulations of a design based on the secondary electron emission from thin C-foils in transmission mode which shows that significant improvements in time resolution can be made with resolutions ∼200 ps being in principle possible. 相似文献
120.
A. Shaporenko A. Terfort M. Grunze M. Zharnikov 《Journal of Electron Spectroscopy and Related Phenomena》2006
Analysis of photoemission spectra of complex thioaromatic self-assembled monolayers (SAMs) requires the knowledge and understanding of such spectra for the basic systems. Keeping this goal in mind, synchrotron-based high-resolution X-ray photoelectron spectroscopy was used to characterize SAMs formed from the simplest thioaromatic compounds, namely thiophenol, 1,1′-biphenyl-4-thiol and 1,1′;4′,1″-terphenyl-4-thiol on evaporated Au(1 1 1) and Ag(1 1 1) substrates. The acquired S 2p and C 1s spectra were analyzed in terms of fine structure and initial and final state effects in the photoemission process. The assignment of the individual spectral features was considered in detail. Conclusions on quality and chemical and structural homogeneity of the investigated SAMs were derived. 相似文献