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61.
Writing a superlattice with light forces 总被引:1,自引:0,他引:1
Th. Schulze B. Brezger R. Mertens M. Pivk T. Pfau J. Mlynek 《Applied physics. B, Lasers and optics》2000,70(5):671-674
In atom lithography the conventional roles played by light and matter are reversed. Instead of using a solid mask to pattern
a light beam, a mask of light is used to pattern a beam of neutral atoms. In this paper we report the production of different
chromium dot arrays with quadratic symmetry. The lattice period depends on the relative polarization and the phase of the
two standing waves generating the light mask. A small angular misalignment of the laser beams breaks the high symmetry and
a chromium superlattice is written, that is a continuous periodic change between two different quadratic lattices. The structures
exhibit lines with a FWHM below 50 nm and clearly separated chromium dots with a FWHM below 70 nm.
Received: 30 September 1999 / Revised version: 14 February 2000 / Published online: 5 April 2000 相似文献
62.
A. Naoumidis H. Beske H. Holzbrecher H. Nickel und H. A. Schulze 《Fresenius' Journal of Analytical Chemistry》1987,329(2-3):278-284
Summary The characterization of oxide scales by their composition and structure is necessary in order to predict their protective behaviour for the high temperature alloys in various corrosive media. For this purpose information obtained by classical methods, such as metallography, X-ray diffraction and microprobe analysis can be supplemented by depth profiles determined by various spectroscopical methods.In this paper, HASTELLOY X und INCONEL 617 were oxidized for relatively short times in two different atmospheres. Depth profiles were determined by GDOS (Glow Discharge Optical Spectroscopy), SNMS (Secondary Neutral Mass Spectrometry) and SIMS (Secondary Ion Mass Spectrometry).The measured profiles were compared with the results of non-destructive X-ray diffraction analysis to characterize the scales and the oxide-metal interface. 相似文献
63.
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65.
Spin correlations of top quarks produced in hadron collisions have not been observed experimentally with large significance. In this Letter, we propose a new variable that may enable demonstration of the existence of spin correlations with 3–4 σ significance using just a few hundred dilepton events both at the Tevatron and the LHC. Such number of dilepton events has been observed at the Tevatron. At the LHC, it will become available once integrated luminosity of a few hundred inverse picobarns is collected. 相似文献
66.
This paper discusses the refinement of multibody models by integration of flexible bodies and by considering nonlinearities from contacts. It presents common approaches for contact modeling in multibody simulations and strategies to include flexible bodies. A contact model is implemented in the elastic multibody model. Experimental results show that significant effects of system dynamics can be modeled by use of a multibody model including elastic bodies and contacts. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
67.
The goal of this paper is to establish the existence of a foliation of the asymptotic region of an asymptotically flat manifold
with positive mass by surfaces which are critical points of the Willmore functional subject to an area constraint. Equivalently
these surfaces are critical points of the Geroch–Hawking mass. Thus our result has applications in the theory of general relativity. 相似文献
68.
69.
Mathias Schulze 《manuscripta mathematica》2007,123(4):373-379
From the degree zero part of the logarithmic vector fields along analgebraic hypersurface singularity we identify the maximal
multihomogeneity of a defining equation in form of a maximal algebraic torus in the embedded automorphism group. We show that
all such maximal tori are conjugate and in one–to–one correspondence to maximal tori in the linear jet of the embedded automorphism
group. These results are motivated by Kyoji Saito’s characterization of quasihomogeneity for isolated hypersurface singularities
[Saito in Invent. Math. 14, 123–142 (1971)] and extend previous work with Granger and Schulze [Compos. Math. 142(3), 765–778 (2006), Theorem 5.4] and of Hauser and Müller [Nagoya Math. J. 113, 181–186 (1989), Theorem 4]. 相似文献
70.
Summary A gas-liquid separator is presented, which is adapted to the special conditions of metalorganic speciation analysis by HPLC-hydride AAS. 相似文献