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Structural parameters and physical properties are considered for >100 presently known simple and binary acentric telluride crystals. Distribution of the crystals over point symmetry groups has been defined in comparison with that of selenides. A rosette of ellipses of acentricity has been outlined on the plane of the shortest chemical bond lengths metal-tellurium in the crystal lattice. A set of...
A method for calculating the refractive index of optical fused silica is proposed and realized. Fused silica is treated as a composite medium with nanopores in matrix with density differing from the crystalline quartz density. Maxwell Garnett model of effective dielectric permittivity is found to be accurate within 0.0002.
We report on a bistable light transmission through a planar metamaterial consisted of a metal pattern of weakly asymmetric elements placed on a nonlinear substrate which enables sharp resonance response by excitation of a trapped mode. A feedback required for bistability is provided by the coupling between strong trapped mode resonance antiphased currents exited on the metal elements and an intensity...
In this paper we propose an efficient numerical technique to model the propagation of an ultrashort pulsed optical beam in dispersive dielectric medium. The method has been efficiently used for the modeling of non-dispersive medium. A moving numerical time window along the propagation of the field allows large saving of computational time and memory in comparison with the conventional FDTD to solve...
A fractal-like (Cantor-like) stratified structure of chiral and achiral isotropic layers is considered. Peculiarities of the wave localization, scalability and sequential splitting in the reflected field of both co-polarized and cross-polarized components are studied. The appearing of the additional peak multiplets in stopbands is revealed, and a correlation of their properties with chirality parameter...
The transformation of an incident plane harmonic wave caused by instant creation of a plasma sphere is investigated. Two stages of field evolution is shown. At the early stage a spatial and temporal field structure is similar partly to the case of an unbounded medium. Transients in the form of a nonstationary wave spectrum are observed at the second stage. The exact expressions for the transformed...
This work is focused on the quick determination of characteristics of the atmospheric transmission media in optical band. Optical wireless links are briefly introduced. Two of the most important effects influencing optical signal properties in the atmosphere are shortly described. The goal of the work is in analysis of optical intensity profile. Due to the changes in the intensity profile we are able...
The process of optical formation of dielectric waveguiding structures in transparent photopolymerizable composition (PPC) containing non-polymerizable component (NC) is considered. It is shown, that using NC does not break modes of influencing radiation self-channeling, and on the contrary, allows to provide conditions of matching of the synthesized waveguiding structures with optical fibers. Results...
The properties of the optical connection of single-mode fibers by laser beams counter-propagating from the ends of these fibers are considered numerically and experimentally. It is established that effective connection of single-mode fibers at the wavelength of 1.55 μm is possible during self-channeling and interaction of optical beams at 0.63 μm in a photo-polymerizing medium. It is shown by computer...
In this paper the results of calculations and optimization of parameters of concave holographic diffraction grating for use in WDM multi/demultiplexer for data transmission systems with polymer optical fibers are presented.
We study de nonlinear optical properties of three ionic liquids of family [BMIM]. The ionic liquids are 1-buthyl-3-methylimidazolium tetrafluoroborate, 1-buthyl-3-methylimidazolium trifluoroacetate, and 1-buthyl-3-methylimidazolium Bis((trifluoromethyl)sulfonyl)imide. We calculate the static molecular polarizability (α) and hyperpolarizability (β,γ) using PM3 model and determinate experimentally the...
The variational method is employed to study the evolution of two adjacent solitons propagating in a strongly dispersion-managed, periodically amplified, single channel optical fiber, in the strong management regime. We study third-order-dispersion (TOD) effects in terms of pulsewidth and center pulse position finding that TOD stabilizes the transmission characteristics and also provides an additional...
Electrical dc conductivity and laser damage threshold of pure and urea doped KH2PO4 crystals are investigated. It is found that the crystals with a low electrical conductivity have a high laser damage threshold. It is shown that increase of the resistivity and the laser damage threshold of the crystals realizes by the crystal growth from urea-containing aqueous solutions. The optimum molar value of...
An automatic control technique of the cross-section microstructured optical fibers geometrical parameters is developed. This method can be used both in the control preform and in the process of drawing into an automated process control system for identify and predict the occurrence of the defect.
In this report results of modeling and experimental researches of the photonic crystal fibers positioning control method based on the analysis of a measured optical field intensity and calculation of its discrete values autoconvolution are represented. Efficiency and accuracy of a method were checked by test image moving on the set size supervised by the certified measuring instrument of small moving.
Structural parameters and physical properties are tabulated for >100 presently known simple and binary acentric chloride crystals. Distribution of the crystals over point symmetry groups has been defined in comparison with that of fluorides. A rosette of ellipses of acentricity has been outlined on the plane of the shortest chemical bond lengths metal-chlorine in the crystal lattice. A combination...
Approximate theory of interaction of optical waves with pure reflection gratings at fulfillment of the second and third orders Bragg conditions has been developed. Expressions of the reflectance were obtained. The start-oscillation conditions in gratings with amplification were searched. It is found that reflectance zeros are near generating modes of grating with amplification in gratings without...
Temperature and humidity-sensitive thick-film structures based on spinel semiconducting ceramics different chemical composition (Cu0.1Ni0.1Co1.6Mn1.2O4 and Cu0.1Ni0.8Co0.2Mn1.9O4) and dielectric magnesium aluminate MgAl2O4 ceramics were fabricated and studied. These elements are shown to be successfully applied for integrated temperature/humidity sensors of environmental monitoring and control.
Optical properties of both symmetrical and asymmetrical modified Fibonacci structures of chiral and achiral isotropic layers are studied. The localization and polarization transformation of linearly polarized waves are considered. The effect of the phase shift compensation in the reflected field is shown in the case of an asymmetrical modified Fibonacci multilayer.
We considered the possibility of the creation of Faraday rotator for optical switch on the basis of ferrite-garnet film with the "angular phase" magnetic anisotropy. The Faraday effect was researched under the extending of light in the plane of the film in the direction of the plane projection on axis of hard magnetization. Under the magnetization of the film by the field saturation of ≈50...
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