Kharkov National University
V.N.Karazin
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1.  Multifunctional measuring platform for investigations parameters of metal-dielectric structures
V.A. Katrich, D.V. Mayboroda, S.A. Pogarsky, I.I. Saprykin
automation complex, dielectric image guide, Energetic characteristics
Vestnik KhNU 712 Pages. 21-24

The multifunctional automation measuring platform for ultra high frequencies parameters definition has been de- signed. The basis of this complex is the controlled mechanical platform which allows to measure the field amplitudes along two orthogonal coordinates. The processing of measuring date realizes with the help of special software. The measuring of energetic characteristics of radiating module based on dielectric image guide has been carried out



2.  Longitudinal slot radiators cut in circular waveguide
E.Y. Belogurov, V.A. Katrich, V.A. Lyaschenko
circular waveguide, axial slot, Electromagnetic waves, radiation, slot antennas
Vestnik KhNU 712 Pages. 37-41

Using method of magnetomotive forces investigations of behaviors of longitudinal slots that were cut in wall of the circular waveguide were carried out. Expressions of internal self-admittance and transfer conductance were de- rived. The possibility of creation of a tapered illumination that forms radiation pattern with low side lobes on long slot cut in circular waveguide was shown



3.  Application of the digital holographic interference microscope for investigation of human red blood cells 3-D morphology
T.V. Tishko, V.P. Titar, D.N. Tishko
digital holographic interference microscope, Erythrocyte, morphology, sphericity coefficient, diagnostics, micro-object
Vestnik KhNU 712 Pages. 52-55

Results on the digital holographic interference microscope for 3-D imaging of native blood erythrocytes are presented. Blood samples of healthy people and patients with different pathologies were used. Three basic morphology kinds of blood erythrocytes were detected. A sphericity coefficient was used as quantitative characteristics of blood erythrocytes morphology. It is shown that, blood erythrocytes 3-D morphology is very important diagnostics characteristics in medical practice. The digital holographic interference microscope is an effective device for the purposes of medical diagnostics



4.  Integral representation of green function in parallel-plate and rectangular waveguide, and in resonator as well
V.A. Katrich, F.S. Novokhatsky
waveguides, Green function, fundamental solution, radial function, Elliptical teta- function, image method, calculus of residues, integral transformation, grating, formal variative
Vestnik KhNU 712 Pages. 67-70

The known results connected with Green function representation by elliptical theta-function are generalized. New representations of Green function for some widely used types of waveguides are obtained. Earlier, these Green functions are presented either in form of series with nonuniform convergence or in form of integrals containing Hancel functions, which are reduced to asymptotic expressions in far zone. On this work integral representations of Green functions are obtained for Cases where the quadrature formula exists. The method of analytical continuation with parameter is applied



5.  Analytical solutions in time domain for electromagnetic fields in a cavity with Debye medium
M.S. Antyufeyeva
dielectric, dispersion, Debye medium, Electromagnetic fields in a cavity with a dielectric, Evolutionary approach to electromagnetics, time domain
Vestnik KhNU 712 Pages. 84-90

The theoretical investigation of the properties of electromagnetic oscillations in a cavity with Debye medium is carried out. The problem is considered within the frame of the Analytical Approach to Electromagnetics in the Time Domain (TD), which allows obtaining closed-form solutions in TD for a wide range of electrodynamical problems. For the description of electromagnetic properties of the medium is used representation of the constitutive relation in an integral form. The analytical solutions are obtained for the several excited functions in TD and they validity conditions are defined. Characteristics of electromagnetic oscillations are presented for different relaxation time and dielectric susceptibility



6.  On experimental substantial of special relativity theory
A.P. Volchenko
competing hypotheses in the Lorentz transformations treatment, Experiments in their testing
Vestnik KhNU 712 Pages. 100-110

Competing hypotheses in the Lorentz transformations treatment mentioned in works of H.Puankare have been considered. Experiments in such hypotheses testing have been commented upon. The conclusions are made about insufficient experimental substantiations of the competing hypotheses accepted in special relativity theory. Alternative definition of the Lorentz transformations and relativity mechanics equations have been specified.



7.  GaAs-Gunn diodes with small levels of power constitution for mm-range oscillators
E.D. Prokhorov, A.V. Dyadchenko, N.E. Polyansky
Gunn diodes, microwave powers, Efficiency, generators mm-range
Vestnik KhNU 712 Pages. 115-118

Experimentally investigated small level operating power GaAs generators mm-range. Samples of diodes made in Problem laboratory of semiconductor engineering of the Karazin Kharkov National University. GaAs -Gunn diodes oscillators operated in continuous mode. The obtained experimentally operated powers made 10...30 mW, the useful microwave powers - 0,1...0,3 mW at an efficiency of 1...2 % over the range frequencies of 60...75 GHz. Probably further reduction consumed by diodes and oscillators of power up to hundreds and tens 10-3W



8.  Stimulation of the size evolution of the gas includes in a liquid by electromagnetic waves
B.G. Yemets
Electromagnetic waves, air bubbles in liquid, temperature field, convection
Vestnik KhNU 712 Pages. 127-131

Based on the model considerations it was shown that irradiation of liquids containing gas inclusions with electromagnetic fields of "slowly-convective" intensity is conducive to the changes in the inclusion size



9.  EXCITATION OF AN UNCLOSED CONE PLACED AT AN IMPEDANCE PLANE
V.A. Doroshenko, O.G. Litvinova, A.V. Sova
Excitation, an impedance plane, cone, longitudinal slots, analytical solutions
Vestnik KhNU 756 Pages. 42-46

By using the approach that is based on applying the Kontorovich-lebedev integral transforms method and a semi-inversion method an excitation boundary problem for a cone with periodical longitudinal slots provided that cone placed at an impedance plane is investigated. It is showed that the problem under consideration is equivalent to solving a system of linear algebraic equations for Fourier coefficients of electromagnetic field components. Analytical solutions are obtained for a semi- transparent cone and special plane impedance. Impedance plane effects are studied



10.  INFLUENCE of ENVIRONMENT ON the FIELD, SCATTERING ON the LATTICE WITH LAYER, AT ANY FALL of the WAVE
A.I. Adonina, V.B. Khokh
lattice, Environment, dielectric, a stream of capacity, method of Riman-Hilbert problem
Vestnik KhNU 756 Pages. 51-56

The decision of a task in view is carried out for and the fields appropriate to two subsystems on which the system of the equations of the Maxwell for environments is divided. Integrated characteristics of a field are determined from the decision of systems of the linear algebraic equations received by a method of method of Riman-Hilbert problem , for a case when the smallest parameter decreases in inverse proportion to a square n->infinity. Programs (fort) with construction of diagrams are made. The analysis of the diagrams in part given in work, allows to establish influence of parameters of structure and corners of fall of a wave on anomalies in an absent-minded field for each concrete case



11.  Electrons in superlattice with continuous conduction band edge
M.V. Klymenko, S.I. Petrov
superlattice, Effective mass, Bragg effect, carriers confinement
Vestnik KhNU 756 Pages. 91-96

In this paper, the energy spectrum of electrons is investigated for the superlattice with continuous conduction band edge. The comparison with conventional superlattice has been realized. It is shown that in the investigated structure the energy spectrum has band structure which is caused by periodic position-dependent effective-mass. Moreover, position-dependent effective-mass leads to additional effective potential. The Bragg reflection for electrons in ballistic limit can be observed in the superlattice with continuous conduction band edge. It can be used for effective Bragg confinement of carriers. For the first time the investigations have been carried out for the case when the superlattice without band offsets has finite number of periods. The obtained results shed light on new applications of the investigated structures for THz frequency range



12.  Wide range mm-wave GAAS- oscillator with electronic frequency gliding
A.V. Dyadchenko, E.D. Prokhorov
oscillators, Electronic frequency gliding, oscillating efficiency
Vestnik KhNU 756 Pages. 101-104

The wide range mm - wave GaAs oscillators with electronic frequency gliding are considered. The oscillator is operated up 60 to 70 GHz on second harmonic. The electronic gliding is perfomed to obtaine of 9 GHz change of frequency



13.  SELECTIVE excitation of the HIGH-order MODES IN THE waveguide quasioptical RESONATOR
A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov
waveguide quasioptical resonator, Excitation of the high-order transverse modes, an amplitude filter, Fourier optics
Vestnik KhNU 756 Pages. 123-131

The method of the space Fourier-filtration for selective excitation of separated high-order transverse modes in the waveguide quasioptical resonator with a high discrimination degree of undesirable modes is proposed and realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes of the dielectric and metal resonators of the submillimeter laser from geometric sizes of reflectors and parameters of the space filter on the nonuniform mirror. Configurations of the amplitude-stepped mirrors for shaping the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed



14.  CALCULATION and EXPERIMENTAL MEASUREMENT OF ANODE BLOCKS PARAMETERS OF MAGNETRONS
K.M. Basrawi, G.I. Churyumov
magnetron, anode block, Q quality factor, loaded Q factor, Equivalent capacity, mode
Vestnik KhNU 756 Pages. 132-138

In this paper the outcomes of calculation and experimental measurements of cold parameters of the pulse and continuous X - range magnetrons are presented. The measuring and calculation techniques of equivalent capacities of the anode blocks of the magnetrons as well as Q quality factor, loaded Q factor and external Q factors of the resonant system for main N/2 - mode and nearest N/2 -1 and N/2 -2 -modes is given



15.  On the primary mechanism for microwave therapeutic effects arising during gamma ray pathology
B. G. Yemets
Electromagnetic microwaves, gamma rays, air bubbles, biologically active points
Vestnik KhNU 756 Pages. 139-143

The biologically active points (BAP) show an increase in size due to an increase in size of air bubbles at near-membrane water layer in the biologically active point cells. The increase in the air bubble size is produced by sweeping the microwave frequency.



16.  Mode basis method for open dielectric waveguide
A. Butrym, M Legenkiy
mode basis method; open waveguide, Eigenmode
Vestnik KhNU 806 Pages. 44-47

The Mode Basis Method construction for the rectangular waveguide with the dielectric insertion when one of the walls of the waveguide is removed to the infinity is considered. Spectrum division into the discrete (surface waves) and continuous parts is analyzed. The range of the continuous change of the spectrum parameter, the presence of the accumulation point and the finite numbers of the discrete modes is revealed. The formulae of the field expansion over the eigenmode of the structure are obtained.


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17.  Theory of the millimeter waves o-type clinotron amplifier
E.N. Odarenko, A.A. Shmat'ko
nonlinear multidimensional theory, clinotron amplifier, Electrons settling
Vestnik KhNU 806 Pages. 75-81

Nonresonant amplifier O-type system with inclined focusing field is considered. Theoretical investigation is carried out within the framework of the beam-wave interaction multidimensional model. Input signal power, focusing field magnetic induction value and electrons settling on the electrodynamical system surface are taking into account


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18.  Selection of the high-order modes in the waveguide resonator by means a phase-shifting mirror
A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov
waveguide quasioptical resonator, Excitation of the high-order transverse modes, a phase filter, Fourier optics, selection
Vestnik KhNU 806 Pages. 87-91

The method of the space Fourier-filtration for selective excitation of separated high-order modes in the metal waveguide quasioptical resonator with a high discrimination degree of undesirable modes is realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes for the metal resonators of the submillimeter laser from resonator geometric sizes and parameters of the phase filter on the nonuniform mirror. Configurations of the phase-shifting mirrors for shaping of the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed


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19.  Increase of free volume 0f the aip abundant in the water by the millimeter waves of low intensity
B. G. Yemets
Electromagnetic waves, air bubbles, field of temperature, convection
Vestnik KhNU 806 Pages. 103-106

Using an NMR technique the volume growth of the free ("bubble") air contained in water caused by low-intense electromagnetic waves is obtained. This change is caused by rectified diffusion of the dissolved air mass into bubbles. The increase in the free air may occure only under those conditions when there is no convection in the liquid, i. e. in the case of irradiating by means of low-intense waves.


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20.  Fields of the rectangular loop antanna in near-field zone
N.N. Gorobets, .V. Trivaylo
Electromagnetic waves, radiation, near-field zone, Hertz vector, traveling wave antenna, loop antenna
Vestnik KhNU 834 Pages. 18-24

On the basis of potential Hertz technique the expressions for calculating of all components of electromagnetic radiation fields of rectangular loop antenna, stimulated by the running wave of the current in Spherical and Cartesian coordinate systems unrestricted on the size of radiator and distance up to a point of observation have been derived. It has been shown that in a near field zone of radiation electromagnetic vectors in the Cartesian and Spherical coordinate systems have all 6 component. It has been shown that wave processes near by the examined radiators are distinguished by great gradients of amplitudes of the electromagnetic fields


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21.  Features of the calculation of Fock-type integrals
V.I. Vyunnik, A.A, Zvyagintsev
Fock-type integrals, numerical integration, Error estimate
Vestnik KhNU 834 Pages. 52-62

Calculation of Fock-type integrals, used at the solutions of the diffraction problems on convex bodies is considered. The method of calculation of this integrals is described, and the estimation of their convergence is given. Range of values of the complex parameter, describing a surface impedance, for which the given method is applicable is determined. The estimation of the error of calculation is carried out


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22.  Radiation of short pulses from the open end of waveguide
O.M. Dumin, O.O. Dumina, V.O. Katrich, Zheng Yu
transient field, modal basis method, Evolutionary equations, impulse field irradiation
Vestnik KhNU 834 Pages. 63-67

The problem of transient electromagnetic field radiation from the open end of waveguide is solved in time domain by the analytical and direct numeral methods. The problem of impulse signal propagation in regular waveguide is converted to the finding of transient wave propagation operator by modal basis method. The application of the operator for the obtaining of time form of signal both for the time change in positive and in the negative direction permits to seek an arbitrary time dependence of field amplitude in any point of waveguide taking into account distortions due to wave dispersion. The correction of diffraction distortions of time form of wave and forming the short probe impulse on the waveguide aperture by the excitation of waveguide in the given cross-section by field with the previously calculated time dependence are considered . Numerical simulation of short impulse irradiation of layered medium with losses is carried out


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23.  Directivity characteristics of rarefied antenna arrays
N.N. Gorobets, A.A. Bulgakova
Electromagnetic waves, antennas, antenna array, directivity characteristics
Vestnik KhNU 834 Pages. 89-94

The radiation pattern, directive gain and scattering coefficient of equivedistance linear array were calculated and their dependencies on the number of radiators and distances between them were analyzed. It is shown that for every number of radiators the optimal antenna length of L≈0,9(N-1), allowing to obtain the maximum of directive gain, occurs. For greater antenna length or increase in operating frequency, directive gain varies according to oscillating dependencies. The greater number of radiators occurs, the greater difference of maximums and minimums occurs. For small number of radiators (N≤8), the directivity characteristics of the array is higher, then for continuous antennas of the same electrical length. For N≥16, their characteristics coincide


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24.  Features of radiation defect formation in kdp crystals under different kinds of irradiation
A.N. Levchenko
KDP single crystal, UV, ionizing irradiation, radiation centers, ESR
Vestnik KhNU 834 Pages. 95-99

Formation processes of different types of radiation paramagnetic centers in potassium dihydrogen phosphate (KDP) single crystals under ultraviolet (UV), gamma-, electron, neutron and proton kinds of irradiation have been investigated with the help of electron spin resonance (ESR) method. The dose dependencies of the relative concentration of the impurity electron centers containing arsenic ions and hole-like centers with the hole localized on the p-orbit of oxygen ion have been measured. The comparison of the effects of the different kinds of irradiation on the radiation paramagnetic defect formation processes has been carried out


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25.  Cathode static domen in transfer electron devise
. V. Botsula, D.V. Pavlenko, E.D. Prokhorov
static domen, velocity field characteristic, Electric field strange
Vestnik KhNU 834 Pages. 104-107

The diode in which static cathode domen and under certain conditions impact ionization takes place has being considered. Transit time effect and noise oscillations takes place under impact ionization. The volatge to be lead to electric field strange abow 200 /sm (for gomogenues velosity field characteristic in ower dides) have been derermened


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26.  Pulse water insonification for laboratory research of electromagnetic wave propagation and dispersion in randomly inhomogeneous media in order to meet the conditions close to working ones
V.B. Yuferov, A.N. Ponomarev, E.V. Mufel, A.N. Ozerov, I.V. Buravilov, V.N. Ishenko
Electromagnetic wave propagation, inhomogeneous medium, air bubbles in liquid, acoustic pulse pneumatic radiator
Vestnik KhNU 834 Pages. 114-119

The efficiency of pulse water insonification by pneumatic radiator is shown. Such radiator enables the formation above the water surface of hydrometcors and aerosols with a desired concentration. It is necessary for laboratory research of fluctuation phenomena of the electromagnetic wave propagation in randomly inhomogeneous media. The use of pneumatic radiator makes possible lo remove salt from the solution. This enables a certain degree of control over liquid permittivity


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27.  Potential of a spherical segment which is placed within a spherical layer with circular aperture.
V.A. Rezunenko
Electrostatics, spherical segment, layer, Fredholm integral equation
Vestnik KhNU 834 Pages. 120-126

The rigorous solution of an axially symmetrical electrostatics problem is obtained. The potential of an ideal spherical segment, which is placed within a spherical layer with circular aperture, is analyzed. We use the methods of regularization, separation and inversion of summarized equations, the method of residues in singular points of analytical functions, the methods of contour integrals and integral transformations. Fredholm integral equation of the second kind with a compact operator in Hilbert space L2 is obtained. The comparison with known results and limit variants is given. The effectiveness of the constructed algorithm is confirmed. Some generalizations of the problems are considered


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28.  Influence of aperture-illumination law on near-field characteristics of aperture antennas
E.E. Ovsyannikova, A.V. Shishkova, N.N. Gorobets
Electromagnetic waves, reactive fields, aperture radiators, Kirchhoff technique, near-field, far-field, amplitude distributions, phase characteristics, amplitude characteristics, reactive radiation power
Vestnik KhNU 853 Pages. 28-36

On the basis of Hertz potentials the investigation of near-field reactive region of square aperture antennas with various aperture illumination laws has been carried out. The influence of the field amplitude distribution law in the aperture on the extension of this region has been studied. The calculation and analysis of amplitude, phase and power radiation characteristics, including reactive radiation power density, at the different planes in near-field region have been carried out. The analysis of the criteria for estimation of near-field reactive region boundary has been carried out


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29.  Paramagnetic properties of ASO2" free radical in irradiated KDP single crystals
A.N. Levchenko
KDP single crystal, ionizing irradiation, free radicals, EPR, spin Hamiltonian
Vestnik KhNU 853 Pages. 84-87

The electron paramagnetic resonance (EPR) spectra of AsO22- free radical in potassium dihydrogen phosphate (KDP) single crystals irradiated with gamma rays and electrons have been investigated. The angular dependences of the spectra have been measured. The number of magnetically inequivalent sites for the AsO22- in the crystal lattice of KDP has been determined. The principal values of g-factor and hyperfine structure tensor have been calculated. It is found that the radical exhibits orthorhombic symmetry. The lagest component of hyperfine tensor is in the ab crystal plane. The molecular planes of the free radicals and the ab crystal plane are mutually perpenducular. The superhyperfine structure of the spectra indicates an existence of two protons near the paramagnetic center


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30.  Random inhomogeneous liquid medium as a continuous laser of low-intensity modulator for excitating sound in the medium
B. G. Yemets
laser, random inhomogeneous liquid medium, interference, temperature field, optical acoustical phenomenon, sound, Excitation, modulation
Vestnik KhNU 853 Pages. 95-100

When a medium is irradiated by laser pulses, sound waves are excited in this medium, i.e., the well-known optical acoustical phenomenon occurs. To excite sound oscillations, the specific laser beam modulator is shown to be unnecessary. The role of the modulator can play the liquid itself, which is a random inhomogeneous medium. The real liquid contains suspended solids and gas bubbles of small dimensions (dust particles and the like) that move irregularly in space (fluctuations). As a result, the electromagnetic wave interference taking place in the liquid undergoes random changes. Consequently, the temperature field changes, and hence variations in the local pressure occurs (thermo-optical mechanism for exciting sound). The excitation of sound due to the laser irradiation of low intensity is observed in an increase in the gas bubbles dimensions in the liquid


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31.  Construction of mode basis for open dielectric structures by integral equation method
Legenkiy M.N., Butrym A.Yu.
mode basis method, open waveguide, Eigenmode
Vestnik KhNU 883 Pages. 50-53

A new method based on integral equation formulation is proposed for construction of mode basis in open dielectric waveguides. Decomposition of the spectrum in such structures into discrete (surface wave) and continuous (volume wave) part is analyzed. Disp


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32.  Ballistic electronic transport in continuous-band superlattice under applied electrostatic field
S.I.Petrov, Klymenko M. V., Shulika O. V.
ballistic transport, superlattice, Effective potential
Vestnik KhNU 883 Pages. 12-19

We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electrostatic field on the electro


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33.  Compromising emanations: overview and system analysis
N.N. Gorobets, .V. Trivaylo
compromising emanations, near-field-zone, Electromagnetic, radiation, time domain
Vestnik KhNU 883 Pages. 83-88

The problem of compromising radiation of spurious signals in the near, intermediate and far zones of observation in time domain are considered. The Compromising emanation system analysis for finding spurious radiation is proposed. The goal of the given approach is to speed the development of technical protection of information. In approximation of the given current distribution it has been suggested a solution considering the influence of the near-field effects upon directional characteristics of spurious signals radiation. The application of the new method allows us to investigate compromising of technical means in time and frequency domain.


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34.  Analysis of polarization characteristics of electromagnetic waves in non-orthogonal linearly polarized basis
Gorobets N.N., Chekalin , Chekalina G.N.
lectromagnetic wave, Electric field strength,time-distance curve, harmonic basis, the expansion of the harmonic, the polarization model
Vestnik KhNU 966 Pages. 50-55

We solve the problem of determining the polarization characteristics coefficient of ellipticity and orientation angle of the polarization ellipse and the direction of rotation of the polarization vectors of linearly polarized basis with arbitrary angle between the components of the electromagnetic wave. In the special case of orthogonal linearly polarized basis obtaind solutions coincide with the known one. An algorithm for constructing a model of elliptically polarized waves had been elaborated in this article as the totality of hyperbolic and elliptic circles.


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35.  Polarization and energy characteristics X-slots in the waveguide with the complex load and the dielectric inserts
Blinova N.K., Yatsuk N.N., Selyutin A.V.
-slots , Ellipse coefficient, VSWR level , circular polarization.
Vestnik KhNU 966 Pages. 77-81

The -slots in a rectangular waveguide with the end complex loading and dielectric inhomogeneity at the waveguide input are considered. Calculation and experimental results of power and polarization descriptions are carried out for such systems. The possibilities of polarization and power characteristics of -slot control are investigated. The variation of dielectric inhomogeneity and complex end loading parametors allows to obtain the circular polarization, high radiation coefficient and low VSWR level


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36.  Signal scattering on the meteor trail
Kharchenko H.V.
signal scattering, meteor trail, diffraction oscillations, Electron density, plasma collective interaction, impulse response.
Vestnik KhNU 966 Pages. 90-96

A generalized model of the radiosignal scattering on the meteor trail is proposed. The model allows to take into account the process of formation and development of the meteor trail, and to calculate the scattered signal power change without sharing the meteor trails on underdense and overdense. As input parameters of the model used the physical parameters of the meteoroid - the mass and velocity, which determine the ionization of the plasma formation, as well as the location and orientation of the meteor trail. In the derivation of the analytical relations taken into account the presence of the plasma sheath surrounding the 'metal cylinder' and the collective interactions in the plasma. In the paper shown that the results of calculations are in good agreement with observations.


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37.  

Earthquakes, VLF emissions, total electron content, Equatorial anomaly
Vestnik KhNU 966 Pages. 103-110

Observational data about variations in VLF emissions and ionospheric total electron content near and at large distances from earthquake areas have been analyzed. The diurnal and day-to-day VLF variations have been shown to have features that correlate with variations in global seismic activity. The effects in the VLF variations occur both prior to enhancements in seismic activity (with the time lag proportional to the earthquake magnitude) and during first 24 h after the earthquake. The effect of violent earthquakes on latitudinal dependence of the total electron content may differ; specifically, the equatorial anomaly can disappear at distances of more than 6,000 km from the epicenter.


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38.  

ballistic transport, superlattice, Effective potential
Vestnik KhNU 883 Pages. 12-19

We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electro-static field on the electron transport leads to new undiscovered phenomena. We consider transport at the center of the Brillouin zone as well as off-center-zone transport. Results obtained open possibility for control of electron transport in semiconductor superlattices.


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39.  Compromising emanations: overview and system analysis
N.N. Gorobets, A.V. Trivaylo
compromising emanations, near-field-zone, Electromagnetic, radiation, time domain
Vestnik KhNU 883 Pages. 83-88

The problem of compromising radiation of spurious signals in the near, intermediate and far zones of observation in time domain are considered. The Compromising emanation system analysis for finding spurious radiation is proposed. The goal of the given approach is to speed the development of technical protection of information. In approximation of the given current distribution it has been suggested a solution considering the influence of the near-field effects upon directional characteristics of spurious signals radiation. The application of the new method allows us to investigate compromising of technical means in time and frequency domain.


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40.  The xecl laser with the adjustable shape and duration of generation pulse
S.S. Anufrik, A.P. Volodenkov, K.F. Znosko
LC- contour, XeCl laser, Excitation system, generation energy, pulse duration.
Vestnik KhNU 983 Pages. 3-10

The generation parameters of LC-contour excitation system are studied for electro-discharge excimer XeCl laser using a NeXeHCl mixture. A computation model is developed for finding the generation parameters. It has allowed us to calculate current, voltage and generation power oscillograms for all parameters of the electrical excitation system. The program of XeCl-laser modeling enables to calculate an electrons, atom and molecule concentrations, specific energy deposition in active medium also. By means of program Bolsig + calculation of rate coefficients of reactions with participation of electrons is executed. It is shown that generation of short radiation pulses (20 ns) and relatively long pulses (60 ns) is possible due to changing of LC- contour parameters. Energy of generation reaches a maximum at use of small values of peaking capacity, which are significantly smaller then value of storage capacity.


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41.  

waveguide resonator, misalignment of the mirrors, terahertz range, Energy losses, mode composition, polarization
Vestnik KhNU 983 Pages. 18-22

The influence of the curvature of the spherical mirror for metallic waveguide resonator of submillimeter laser (lambda = 0.4326 mm) on energy losses and the mode composition of radiation is investigated. It is shown that the presence of quadratic phase aberrations in the mirrors of the waveguide cavity with an increase of its Fresnel number at monotonically decreasing of the energy losses for fundamental asymmetric mode TE11q due to a decrease of waveguide losses also leads to their substantial non-periodic oscillation.


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42.  

grid, bolometer, intensity distribution, polarization, Energy center, beam diameter, generalized cross-sectional square of the beam.
Vestnik KhNU 983 Pages. 72-76

In this paper the grid receiver for measuring laser radiation characteristics has been considered. The receiver contains four grids located perpendicular to the direction of propagation. Wire elements are located at angles 0 , 45?, 90? and 135? to the vertical. One grid contains 8 nickel bolometers with diameter 40 microns, bolometers are located on 7.2 mm from each other. The diameter of the window 60 mm. Intensity distribution in the space has been measured, therefore, the position of the energy center, the diameter, the generalized cross-sectional square of the radiation beam have been determined. The Radon transformation has been used as the mathematical basis of signal processing algorithms. Also the polarization direction and intensity distribution of polarized radiation have been measured by a numerical experiment.


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43.  

wave equation, Exact solutions, localized waves, Bateman solution, general astigmatism.
Vestnik KhNU 983 Pages. 77-83

A new class of exact non-harmonic in time solutions of 3D wave equation is established. This class is a generalization of the known complexified relatively undistorted Bateman-type solution, involving an arbitrary function, waveform. Argument of this function is much similar to that which appears in general astigmatic paraxial Gaussian beam. Special choices of the waveform allow general astigmatic beam-like and packetlike waves with Gaussian-type localization in space and time.


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44.  

plasma, surface plasmons (plasmon resonances), scattering cross section, Eigenvalues.
Vestnik KhNU 983 Pages. 84-90

Plasmon resonances of an isolated plasma cylinder and if a pair of coupled plasma cylinders are theoretically investigated. Mechanism of the plasmonic modes coupling that can be considered as symmetric and antisymmetric combinations of isolated cylinders plasmons is investigated. Accurate analysis of the spectrum of different Plasmon resonances is presented. Significant enhancement of the field in the case of distant cylinders in comparison to isolated one is revealed (separation distance is near 10-20 radii). The calculation accuracy is estimated. Figures show the scattering cross section of plane wave on the isolated plasma cylinder and on the pair of coupled cylinders and the real part of the eigenfrequency of the plasmon modes. Near field spatial characteristics of plasmons are presented.


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45.  

radioholographic image, flat and unflat radiohologram, by volume image of object, Effect of Dopler.
Vestnik KhNU 927 Pages. 48-53

The physical and structural features of construction of the radioholographic informative systems (RG IS) and their adaptive properties which show up at forming and treatment of the coherent wave field on a transmission and reception are examined. The method of registration of radiohologram is offered on the surfaces of arbitrary form and method of adaptation of frequency of supporting oscillation to different frequencies of signal at a cooperative reception and to frequency of Dopler.


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46.  

Gunn diode, dipole domain, accumulation layers, transit frequency, Efficiency generations
Vestnik KhNU 927 Pages. 3-6

Results of research of power and frequency characteristics of Gunn diodes on the basis of Al1-xInxN for various values of concentration of impurity in active area in biharmonic regime are present. It is shown, that using of voltage of the complex form leads to increase of efficiency generation at the basic harmonic in comparison with work in harmonic regime. The increase of impurity concentration in active area leads to increase of efficiency generation both on the first, and on the second harmonic. At the expense of effective work on the second harmonic there is a possibility of reception of generation to frequencies of a submillimetric range.


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