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991.
We have solved a self-consistent problem on interaction of two dipole atoms located at an arbitrary distance from each other
with the field of a quasiresonance light wave, whose intensity is sufficient for the system to manifest nonlinear properties.
The atoms are considered as two-level systems described by means of Bloch optical equations, while the field inside of the
system includes both Coulomb and retarded parts. We consider a situation where atoms are identical and the distance between
them is much smaller than the length of an outer light wave. The distribution of an electric field both inside of a small
object and outside of it is found numerically. It is shown that the amplitude of the electric field in a wave zone depends
substantially on the frequency of the external field and interatomic distance, while the field distribution differs from the
field pattern of an electric dipole. At definite values of the external field intensity an optical multistability is a feature
of the system under investigation. We have elucidated the conditions under which the multistability is manifested in the present
system. The results obtained are considered as the near-field effect in the optics of small objects, which makes it possible
to investigate the structure of small objects by means of optical radiation.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 375–378, May–June, 2000.
The present work was supported by the Russian Foundation for Fundamental Research (grant 98-02-16035) and by a grant from
the Federal Purpose-Oriented Program “Integration.” 相似文献
992.
纤维悬浮流场动力学研究综述 总被引:4,自引:0,他引:4
阐述了纤维悬浮流研究的学术价值及其在实际中的应用,回顾了近10年来该领域的主要研究结果,提出了尚未解决而又非常重要的几个问题,指出了该领域的发展前景。 相似文献
993.
We use the improved Faddeev-Jackiw quantization method to quantize the electromagnetic field and its Lagrange multiplier fields. The method's comparison with the usual Faddeev-Jackiw method and the Dirac method is given. We show that this method is equivalent to the Dirac method and also retains all the merits of the usual Faddeev-Jackiw method. Moreover, it is simpler than the usual one if one needs to obtain new secondary constraints. Therefore, the improved Faddeev-Jackiw method is essential. Meanwhile, we find the new meaning of the Lagrange multipliers and explain the Faddeev-Jackiw generalized brackets concerning the Lagrange multipliers. 相似文献
994.
995.
We study a version of Whitney’s embedding problem in projective geometry: What is the smallest dimension of an affine space that can contain an n-dimensional submanifold without any pairs of parallel or intersecting tangent lines at distinct points? This problem is related to the generalized vector field problem, existence of non-singular bilinear maps, and the immersion problem for real projective spaces. We use these connections and other methods to obtain several specific and general bounds for the desired dimension. 相似文献
996.
We investigate the ratio of spin precession frequency to orbital frequency for a spinning charged particle confined to circular
orbit in the equatorial plane of a compact object, with a uniform magnetic field, as described by the Wald and the Ernst potentials.
In order to see the difference in behaviours for particles with differentg values we consider the cases of electron and proton separately. 相似文献
997.
李子平 《新疆大学学报(理工版)》1987,(3)
本文给出由非不变性拉氏量导致的广义Bianchi恒等式的若干应用。导出强守恒律,用于某些场论,得到相应的弱守恒律,讨论了非不变拉氏量系统的Dirac约束。 相似文献
998.
Marian Slodicka Jan Busa Jr. 《计算数学(英文版)》2008,(5):677-688
This paper is devoted to the study of a nonlinear evolution eddy current model of the type δtB(H) + △↓× ( △↓ × H) =0 subject to homogeneous Dirichlet boundary conditions H × v = 0 and a given initial datum. Here, the magnetic properties of a soft ferromagnet are linked by a nonlinear material law described by B(H). We apply the backward Euler method for the time discretization and we derive the error estimates in suitable function spaces. The results depend on the nonlinearity of B(H). 相似文献
999.
1000.
Ziqiang Yang Chengliang Ge Zheng Liang 《International Journal of Infrared and Millimeter Waves》2000,21(11):1887-1896
Reported in this paper are the results of an experiment to produce high-power microwave radiation from a gas-filled backward wave oscillator (BWO) driven by a relativistic electron beam without external guiding magnetic field. A peak power for background gas pressure at 5.25 mTorr has been observed as argon pressure from 0.75 mTorr to 15 mTorr. Operating frequency of the oscillator has been measured at 9.6 ± 0.4 GHz. The results of PIC simulation are in good agreement with the experimental results. A reasonable explanation is given for experimental results by PIC simulation. 相似文献