Valery I. Grygoruk

• Head of Department at Taras Shevchenko National University of Kyiv

Reconfigurable radio‐frequency components are in high demand for modern communication systems as they can be involved in multiband and multistandard electronic devices. The key part of such components is an active switching element. This work offers a way to obtain an efficient microwave switch using vanadium dioxide‐poly (methyl methacrylate) comp...

Two photochemical nano-polishing techniques for rough quartz surfaces are compared in terms of electrodynamics. The numerical modelling of the evanescent field configuration near the quartz surface is considered. The finite-element approach is used to solve the Helmholtz two-dimensional vector equation. The quartz surface coated with a liquid conta...

The spectroscopic analysis of the frequency distribution of the amplification of optical radiation due to the Raman effect (Raman gain profile) in single-mode fibers based on silica glass has been carried out in the region of Stokes frequency shifts from 0 to 1400 cm−1. The Raman gain profiles are determined from the experimental spectra of spontan...

В работе предложена модель диполя со структурой атома вместо стандартной модели диполя с точечными разноименными зарядами и модели диполя Герца, которые имею существенные недостатки. Уравнения диполя Герца и стандартной модели работают от расстояния, намного превышающего размер самого диполя, а квазистатические поля Кулона и Био-Савара являются сут...

The properties of hysteresis of ferro-magnetic resonance frequency-field dependence of barium-hexaferrite samples have been the subject for study. The main objective is to investigate experimentally features of high-frequency magnetic hysteresis in a wide range of thickness of samples. The experimental investigation has been carried out using the E...

In the work, studies of voltage oscillations that occur during the flow of high-density currents through a silicon structure with dielectric insulation (SSDI structure) are carried out. Volt-ampere characteristics of the structure in the pulsed mode, characteristic parameters of the oscillograms of oscillations, both relaxation and quasi-harmonic,...

The processes occurring during the interaction of dipoles in an optical near field are investigated. A method for their calculation is proposed. It is shown that since the spectral composition of the near-field radiation is not monochrome, this makes it possible to effectively influence the dipole structure even by fields that are nonresonant for t...

The destruction of surface nano-inhomogeneities of a quartz substrate using the optical nearfield dipole-dipole interaction of atomic chlorine with SiO2 is studied. A method to obtain atomic chlorine by the local photodissociation of molecular chlorine by the optical near-field of the quartz substrate nano-inhomogeneities is proposed. The polarizat...

In this work we study the properties of hysteresis of ferro-magnetic resonance frequency-field dependence in the samples of barium hexaferrite. The purpose of the study is the experimental investigation into the properties of high-frequency magnetic hysteresis within the wide range of the samples thickness. The experimental investigation was carrie...

The properties of TiO2-doped fiber are considered as optoelectronic material in our work. The advantages of such fiber have been studied with the aim of its application to active medium in Raman fiber lasers. The comparison of spontaneous Raman spectra and corresponding gain profiles in TiO2-doped and GeO2-doped fiber is presented. Raman gain profi...

Bandpass transmission line on the basis of uniaxial single-crystal hexaferrites in multidomain area has been proposed in this paper. This line can be used for experimental investigation of excitation and propagation of magnetostatic waves within millimeter wave range in uniaxial single-crystal hexaferrites as well as for designing of bandpass filte...

Results of experimental research of developed ceramics on the basis of three-component SrO-Al2O3- SiO2 system have been presented. The influence of mineralizing impurities when entering them into stoichiometric composition of ceramics has been proved. Main electromagnetic characteristics of the ceramics have been measured: permittivity, dielectric...

Hybrid electromagnetic-spin oscillations in ferrite-dielectric structure consisting of a single-crystal BaFe12O19 platelet and a dielectric disk-shaped resonator in multidomain state of ferrite have been investigated by experiment. Experiments were conducted with different types of domain structures, and the frequency-field spectra were measured at...

Prototype of bandpass filter based on single-crystal platelet of hexaferrite in multidomain area with stripe domain structure in the initial state was proposed for the first time. Designed and experimentally studied filter has 3dB-bandwidth of 80 MHz within frequencies about 47 GHz in absence of external biasing magnetic field. The filter has inser...

By means of nabla operator written down with using both of some differential operators with integer orders and fractional differential Caputo operators, gradient, divergence and rotor operators are determined, it is checked up the fulfillment of vector relations in fractional vector analysis, fractional Green’s, Stocks’ and Ostrogradsky-Gauss’ form...

A model system to study the mechanisms of light conduction in higher plants is developed. An optimum source of light is selected, and a metallic construction allowing one to change the angle and the intensity of the illumination of plants is produced. On the basis of the KhLMTs-1S device, a system of cuvettes with light filters selecting narrow spe...

We examine in this paper two cases, which are very interested for the theory and experiments: a case of an integrated-optical waveguide with statistic surface roughness and a case of optical nanofibers with random rough surface. The peculiarities of approximate solutions of vector electrodynamic problems in the first cases in brief are discussed an...

The possibility of changes in the polarization state of the laser beam reflected from inhomogeneity with the refractive index gradient is theoretically shown, which allows separating the phase shifts related with relief inhomogeneities and local changes of the surface refractive index. Modification of the wavefront scanner for analyzing the wavefro...

We use the Mueller matrix for inhomogeneous linear birefringent media derived in Savenkov et al. [Mueller-matrix model of an inhomogeneous linear birefringent medium: single scattering case. JQSRT 2007;106:475–86] to generate new results on the forward scattering of light using Cloude's coherence matrix method. We show that the intensity of scatter...

A method of an object surface profile reconstruction from samples of two partial derivatives in perpendicular directions is proposed. The method uses substantial information redundancy for object, which is available in data for both partial derivatives. This allows obtaining adequate reconstruction of the surface profile in the presence of noise. T...

The Mueller matrix model for inhomogeneous medium characterized by simultaneous linear and circular birefringence for single scattering in the forward direction is derived. We find that the presence of inhomogeneity results in the occurrence of new polarization effects. In particular, forward scattering by inhomogeneous birefringent medium exhibits...

This is a study of the effect of the ellipticity of the polarization of radiation at the inlet of the shaping polarizer in the probe channel of a Mueller polarimeter operating with three linear probe polarizations on the accuracy with which the incomplete Mueller matrix is determined (without a fourth beam). It is shown that the appearance of and v...

A modification of the wavefront registration scheme aimed at improving the spatial resolution of a sensor has been considered. A focused laser beam has been proposed for illuminating a researched surface area; after the optical transformation in a Fourier optics scheme, the beam forms a signal in the sensor plane, which could be considered as a pha...