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61.
We describe what we believe to be novel types of discrete cavity solitons in nonlinear waveguide arrays that are driven by an external holding beam. We demonstrate that a holding beam with a definite inclination drives the system in a subdiffractive regime and allows the formation of stable discrete cavity solitons. We predict the existence of both bright and dark moving midband discrete cavity solitons for an identical set of system parameters for both focusing and defocusing Kerr nonlinearities. 相似文献
62.
Umbilic points--singular points of curvature characterized by a fractional topological charge q=+/-1/2--are the most numerous of all special points in the landscape of random optical fields (speckle patterns), outnumbering maxima, minima, saddle points, and optical vortices. To the best of our knowledge, we present the first experimental evidence that positive and negative umbilic points screen one another. Theory predicts that in the absence of screening the charge variance in a bounded region is proportional to the area of the region, whereas in the presence of screening the variance is drastically reduced and is proportional to the perimeter. Our data confirm this latter prediction and provide the first estimates of the screening lengths for umbilic points of the intensity and of the amplitude (field modulus). 相似文献
63.
The circular polarization components of a vortex beam in a uniaxial crystal exhibit complex propagation characteristics. We demonstrate how the amount of splitting may be distinguished by use of a vortex beam. We predict and experimentally verify a threshold angle subtending the crystal and beam axes, below which the splitting is indistinguishable. 相似文献
64.
Volumetric Properties of Aqueous Solutions of Acetamide in the 274.15–333.15 K Range of Temperatures
Makarov D. M. Egorov G. I. Kolker A. M. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(4):693-697
Russian Journal of Physical Chemistry A - The densities of aqueous solutions of acetamide up to a mole fraction of x2 = 0.3875 are measured over a wide range of temperatures (274.15–333.15) K... 相似文献
65.
Lebedev D. V. Egorov V. V. Shvetsov A. V. Zabrodskaya Y. A. Isaev-Ivanov V. V. Konevega A. L. 《Crystallography Reports》2022,67(2):308-308
Crystallography Reports - An Erratum to this paper has been published: https://doi.org/10.1134/S1063774521340034 相似文献
66.
Lebedev D. V. Egorov V. V. Shvetsov A. V. Zabrodskaya Y. A. Isaev-Ivanov V. V. Konevega A. L. 《Crystallography Reports》2021,66(2):242-253
Crystallography Reports - The review describes the application of small-angle scattering (SAS) of neutrons and complementary methods to study the structures of biomacromolecules. Here we cover SAS... 相似文献
67.
Russian Physics Journal - The interaction energy of the ozone molecule with atoms of noble gases (Ar and He) is analyzed. The coupled cluster methods CCSD(T) and CCSD(T)-F12 with orbital basis sets... 相似文献
68.
Vereshchagin Anatoly N. Karpenko Kirill A. Elinson Michail N. Minaeva Alexandra P. Goloveshkin Alexander S. Hansford Karl A. Egorov Mikhail P. 《Molecular diversity》2020,24(4):1327-1342
Molecular Diversity - A novel five-component diastereoselective synthesis of polysubstituted 2-piperidinones is reported. The Knoevenagel condensation–Michael addition–Mannich cascade... 相似文献
69.
70.
A. Yu. Antonov N. V. Egorov L. C. Chao 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2009,3(5):826-832
The problem of determining the coefficient of electron transmission through the potential barrier at the metal-vacuum interface
is considered. The temperature dependence of the thermofield’s current density is studied using methods of mathematical modeling.
The problem is reduced to the solution of a system of algebraic equations. It is shown that regularization of the solution
of the problem is required. The results demonstrate that the coefficient of electron transmission can be determined in principle. 相似文献