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41.
Conventional phase diffraction gratings can be used to localize the incoming optical radiation in the near‐field region. A new design of the binary phase diffraction grating is proposed with embedded pupil opaque mask inside each stripe. By means of numerical simulations, it is shown that with this masked phase grating the spatial resolution of the near‐field localization can be substantially improved and brought even beyond the solid immersion limit (λ/2n). Moreover, due to anomalous apodization effect, the subdiffraction field localization is accompanied by intensity enhancement as compared to the non‐masked design. The pupil mask rearranges the optical fluxes within the stripes and promotes the Fano resonances excitation in the periodic step lattice. This can be important for advancing the phase grating‐based super‐resolution technologies, including subdiffraction imaging, interferometry, and surface fabrication. 相似文献
42.
Fractal Hamilton-Jacobi-KPZ equations 总被引:1,自引:0,他引:1
Grzegorz Karch Wojbor A. Woyczynski 《Transactions of the American Mathematical Society》2008,360(5):2423-2442
Nonlinear and nonlocal evolution equations of the form , where is a pseudodifferential operator representing the infinitesimal generator of a Lévy stochastic process, have been derived as models for growing interfaces in the case when the continuous Brownian diffusion surface transport is augmented by a random hopping mechanism. The goal of this paper is to study properties of solutions to this equation resulting from the interplay between the strengths of the ``diffusive' linear and ``hyperbolic' nonlinear terms, posed in the whole space , and supplemented with nonnegative, bounded, and sufficiently regular initial conditions.
43.
断裂力学中的相似方法 总被引:3,自引:0,他引:3
不论是材料的断裂强度还是结构的承载能力均存在着明显的“尺度效应”.本文旨在较全面且系统地总结断裂力学中的相似方法、无量纲数及其断裂力学中有关的尺度率,并给出作者自己对某些问题的看法和认识 相似文献
44.
We study the dynamics of a Rouse polymer chain which diffuses in a three-dimensional space under the constraint that one of its ends, referred to as the slip-link, may move only along a one-dimensional line containing randomly placed, immobile, perfect traps. Extensions of this model occur naturally in many fields, ranging from the spreading of polymer liquids on chemically active substrates to the binding of biomolecules by ligands. For our model we succeed in computing exactly the time evolution of the probability P
sl(t) that the chain slip-link will not encounter any of the traps until time t and, consequently, that until this time the chain will remain mobile. 相似文献
45.
计算了两个与量子数为JPC=1-+的胶球流算符密切相关的三胶子张量算符Ωαβ1=Gαa,μ Gμb,ν Gνβc fabc和Ωαβ2=gαβ Gσa,μ Gμb,ν Gνc,σ fabc的重整化矩阵和反常量纲矩阵. 相似文献
46.
The diffusion of liquid crystal 4‐n‐pentyl‐4′‐cyanobiphenyl (5CB) into a poly(butyl methacrylate) (PBMA) matrix has been studied using fast FTIR imaging. The concentration profiles were obtained as a function of time at several temperatures above and below the nematic to isotropic transition temperature (TNI) of 5CB and the Tg of PBMA. The time‐dependent progression of the diffusion front position, when fitted to a power law model, exhibited exponential values between 0.40 and 0.52. This, along with the observed progression of a sharp 5CB‐diffusion front into the PBMA matrix, indicates the presence of an anomalous diffusion process. It was shown that fast FTIR was able to correctly identify the diffusion process as anomalous, whereas a simple mass uptake analysis would have led to the conclusion that the process proceeded according to Fick's second law. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2261–2268, 1999 相似文献
47.
电子输运现象包含一系列很重要的材料性质,并可以用来提供关于载体物理系统的很多信息。在
最近的二三十年,人们逐渐认识到除了电子能谱之外,电子在布里渊区的几何性质,比如贝利曲率和
轨道磁矩,会在电子输运中起到关键性的作用。在线性输运现象中的此种关联已引起广泛的兴趣并得
到深入的研究。然而,在非线性输运现象中的电子几何性质的作用的研究最近才逐渐起步。此种关联
可以大大加深对各种非线性输运现象的认识,并对如何从材料控制上调节非线性现象的强度提供有价
值的研究视角和指导原则。基于此背景,本文试图引入研究输运现象的半经典理论框架,并在几种输
运现象中举例说明贝利相的作用。 相似文献
48.
电子输运现象包含一系列很重要的材料性质,并可以用来提供关于载体物理系统的很多信息。在
最近的二三十年,人们逐渐认识到除了电子能谱之外,电子在布里渊区的几何性质,比如贝利曲率和
轨道磁矩,会在电子输运中起到关键性的作用。在线性输运现象中的此种关联已引起广泛的兴趣并得
到深入的研究。然而,在非线性输运现象中的电子几何性质的作用的研究最近才逐渐起步。此种关联
可以大大加深对各种非线性输运现象的认识,并对如何从材料控制上调节非线性现象的强度提供有价
值的研究视角和指导原则。基于此背景,本文试图引入研究输运现象的半经典理论框架,并在几种输
运现象中举例说明贝利相的作用。 相似文献
49.
Wenjia Wang Xiaoyun Yang Guangcai Chang Pengfei An Kewen Cha Yuhui Dong Peng Liu 《Journal of synchrotron radiation》2017,24(4):781-786
A method to calibrate and stabilize the incident X‐ray energy for anomalous diffraction data collection is provided and has been successfully used at the single‐crystal diffraction beamline 1W2B at the Beijing Synchrotron Radiation Facilities. Employing a feedback loop to control the movement of the double‐crystal monochromator, this new method enables the incident X‐ray energy to be kept within a 0.2 eV range at the inflection point of the absorption edge. 相似文献
50.
The explicit form of operators of kinetic momenta and spin projection for a neutral particle with an anomalous magnetic moment in constant homogeneous electromagnetic field is found. The possible applications of the obtained results in neutrino physics are considered. 相似文献