排序方式: 共有19条查询结果,搜索用时 514 毫秒
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Loch RA Dubrouil A Sobierajski R Descamps D Fabre B Lidon P van de Kruijs RW Boekhout F Gullikson E Gaudin J Louis E Bijkerk F Mével E Petit S Constant E Mairesse Y 《Optics letters》2011,36(17):3386-3388
We characterize the phase shift induced by reflection on a multilayer mirror in the extreme UV range (80-93?eV) using two techniques: one based on high order harmonic generation and attosecond metrology (reconstruction of attosecond beating by interference of two-photon transitions), and a second based on synchrotron radiation and measurements of standing waves (total electron yield). We find an excellent agreement between the results from the two measurements and a flat group delay shift (±40?as) over the main reflectivity peak of the mirror. 相似文献
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Voronov DL Anderson EH Gullikson EM Salmassi F Warwick T Yashchuk VV Padmore HA 《Optics letters》2012,37(10):1628-1630
Diffraction efficiency of multilayer-coated blazed gratings (MBG) strongly depends on the perfection of the sawtooth-shaped layers in the overall composite structure. Growth of multilayers on sawtooth substrates should be carefully optimized to reduce groove profile distortion and, at the same time, to avoid significant roughening of multilayer interfaces. In this work, we report on a way to optimize growth of sputter-deposited Mo/Si multilayers on sawtooth substrates through variation of the sputtering gas pressure. We believe a new record for diffraction efficiency of 44% was achieved for an optimized MBG with groove density of 5250 lines/mm at the wavelength of 13.1 nm. 相似文献
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Nachimuthu P Thevuthasan S Adams EM Weber WJ Begg BD Mun BS Shuh DK Lindle DW Gullikson EM Perera RC 《The journal of physical chemistry. B》2005,109(4):1337-1339
Disorder in Gd2(Ti(1-y)Zry)2O7 pyrochlores, for y = 0.0-1.0, is investigated by Ti 2p and O 1s near-edge X-ray absorption fine structure spectroscopy. Ti(4+) ions are found to occupy octahedral sites in Gd2Ti2O7 with a tetragonal distortion induced by vacant oxygen sites. As Zr substitutes for Ti, the tetragonal distortion decreases, and Zr coordination increases from 6 to 8. The migration of oxygen ions from 48f or 8b sites to vacant 8a sites compensate for the increased Zr coordination, thereby reducing the number of vacant 8a sites, which further reduces the tetragonal distortion and introduces more disorder around Ti. This is evidence for simultaneous cation disorder with anion migration. 相似文献
5.
Direct measurement of index of refraction in the extreme-ultraviolet wavelength region with a novel interferometer 总被引:1,自引:0,他引:1
Chang C Anderson E Naulleau P Gullikson E Goldberg K Attwood D 《Optics letters》2002,27(12):1028-1030
To the best of our knowledge, the first direct measurement of the dispersive part of the refractive index is performed at extreme-ultraviolet (EUV) wavelengths, where absorption is higher as compared with hard-x-ray and visible wavelengths. A novel diffractive optical element that combines the functions of a grating and a zone plate is fabricated with Fourier optical techniques and employed here for the first time at EUV/soft-x-ray wavelengths. Both the real and the imaginary parts of the complex refractive indices are measured directly by this technique without recourse to Kramers-Kronig transformations. Data for Al and Ni in the vicinity of their L and M edges, respectively, are presented as first examples of this technique. 相似文献
6.
We have fabricated W/B(4)C multilayers having periods in the range d = 0.8-1.2 nm and measured their soft-x-ray performance near normal incidence in the wavelength range 1.4相似文献
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Muramatsu Y Kaneyoshi T Gullikson EM Perera RC 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(9):1951-1957
Angle-resolved soft X-ray emission and absorption spectra in the BK and NK regions of hexagonal BN were measured using polarized synchrotron radiation. The take-off/incident-angle-dependence on the spectral features in both X-ray emission and absorption is clearly observed. The configuration of the sigma and pi orbitals, which were calculated using discrete variational (DV)-Xalpha molecular orbital calculations, explains the angle-resolved soft X-ray emission and absorption spectra. The relative peak intensity of the 394-eV peak in the NK X-ray emission provides useful information about the BN layer ordering. 相似文献
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14.5% near-normal incidence reflectance of Cr/Sc x-ray multilayer mirrors for the water window 总被引:1,自引:0,他引:1
Eriksson F Johansson GA Hertz HM Gullikson EM Kreissig U Birch J 《Optics letters》2003,28(24):2494-2496
Cr/Sc multilayer mirrors, synthesized by ion-assisted magnetron sputter deposition, are proved to have a high near-normal reflectivity of R = 14.5% at a grazing angle of 87.5 degrees measured at the wavelength lambda = 3.11 nm, which is an improvement of more than 31% compared with previously published results. Elastic recoil detection analyses show that the mirrors contained as much as 15 at. % of N and traces of C and O. Soft x-ray reflectivity simulations reveal interface widths of sigma = 0.34 nm and an exceptionally small layer thickness drift of approximately 1.6 x 10(-5) nm/multilayer period throughout the stack. Simulations show that a reflectivity of R = 25.6% is attainable if impurities and layer thickness drift can be eliminated. The abrupt interfaces are achieved with ion assistance with a low ion energy of 24 eV and high ion-to-metal flux ratios of 7.1 and 23.1 during Cr and Sc sputter deposition, respectively. In addition, a near-normal incidence reflectivity of 5.5% for the C VI emission line (lambda = 3.374 nm) from a laser plasma source was verified. 相似文献
9.
Fabrication of high-efficiency multilayer-coated binary blazed gratings in the EUV regime 总被引:1,自引:0,他引:1
Patrick P. Naulleau Erik H. Anderson Eric M. Gullikson Jeffrey Bokor 《Optics Communications》2001,200(1-6):27-34
Improving the efficiency of soft X-ray and extreme ultraviolet (EUV) gratings by way of multilayer reflection coatings has been under investigation for many years. Here we present the fabrication and characterization of binary blazed gratings designed to operate in the 14 nm wavelength region. These binary gratings are stepped approximations to the ideal sawtooth blazed-grating profile and are fabricated directly into a layer of photoresist. Normal-incidence reflection efficiencies as high as 25% into the first-diffracted order have been demonstrated. 相似文献
10.
Y. Uehara D.W. Lindle T.A. Callcott L.T. Terminello F.J. Himpsel D.L. Ederer J.H. Underwood E.M. Gullikson R.C.C. Perera 《Applied Physics A: Materials Science & Processing》1997,65(2):179-182
3 and L2 resonances, especially strong at the L3 resonance, while inelastic peaks were observed from well below the resonance and showed complex features at the excitation
energies between the Ti L3 and L2 resonances. The measured spectra were explained based on radiative and non-radiative electronic processes near the Ti-L2,3 edge in the titanate.
Received: 6 March 1997 相似文献