1. Millimeter wave rotational spectrum of the lower excited vibrational states of CH_{3}CF_{2}Cl O.I. Baskakov, V.V. Ilyushin, E.A. Alekseev molecule, rotational spectrum, interacting states, Hamiltonian, HCFC142b Vestnik KhNU ¹712 Pages. 39
The millimeter rotational spectrum of CH_{3}CF_{2}CI has been investigated. The rotational, centrifugal distortion and quadrupole coupling parameters have been determined for the vibrational states with energies below 600 cm^{1}. Parameters of the ground and 11^{1}, 17^{1}, 18^{1}, 17^{1}18^{1} and 11^{1} states have been obtained for both chlorine isotopic species. In addition, the 1111, 18^{2}, 10^{1}, 16^{1}, 9^{1} and 11^{1}18^{1} vibrational states have been studied for CH3CF235C1 molecule. It was found the interaction between 10^{1} and 16^{1}, and 9^{1} and 11^{1} 18^{1} couples. The transition frequencies calculated with the parameters obtained coincide with the measured ones within experimental uncertainties.
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 ¹712 Pages. 3741
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 selfadmittance 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. Impedance of connected in series diodes with difference negative conductivity E.D. Prokhorov tunnel diode, negative conductivity, frequency range Vestnik KhNU ¹712 Pages. 111114
The impedance connected in series negative difference conductivity diodes in wide frequency range are analyses. There are frequency region that diodes combination work have been appeared. The operation frequencies for combination of tunnel diodes are 3540 GHz
4. GaAsGunn diodes with small levels of power constitution for mmrange oscillators E.D. Prokhorov, A.V. Dyadchenko, N.E. Polyansky Gunn diodes, microwave powers, efficiency, generators mmrange Vestnik KhNU ¹712 Pages. 115118
Experimentally investigated small level operating power GaAs generators mmrange. 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_{3}W
5. Same question of modeling of tunnel contact semiconductor structure O.V. Botsula, E.D. Prokhorov tunnel cathode, negative differential conductivity, contacts, current  voltage characteristics, cathode, anode Vestnik KhNU ¹712 Pages. 119122
Electronic processes are considered at course of a current through semiconductor structure with the tunnel cathode. The approach to modelling the structures including as a component tunnel geterojunction is offered. Static characteristics of structures to a basis geterojunction GaAs/AIGaAs received with application of the offered technique are resulted
6. The spectrum of current oscillations of Gunn diodes with the impact ionization in moving domains D.V. Pavlenko, E.D. Prokhorov Gunn diode, impact ionization, UHFnoise Vestnik KhNU ¹712 Pages. 123126
The results of the numerical simulation of the GaAs Gunn diode with electric field strengths, enough for development of the impact ionization in the moving highfield domains, are presented. The form of current oscillations and frequency spectrums is in good agreement with experimentally measured data. It is shown that the Gunn diode, operating under conditions of the impact ionization, may be used as a source of wide spectrum UHFnoise
7. ELECTRODYNAMIC MODELING OF COMPOSITE MEDIA WITH SIMALTENEOUSLY NEGATIVE REAL PARTS OF PERMITTIVITY AND PERMEABILITY S.N. Shulga, I.E. Khodasevych composite media, thinwire resonance inclusions, permittivity, permeability, scattering of electromagnetic waves Vestnik KhNU ¹756 Pages. 3841
This paper presents physical and mathematical model and investigation of electromagnetic properties of composite material made of straight and curved conducting resonance inclusions placed into isotropic media and forming periodic lattice. The effective constitutive parameters of the composite material are found. It is revealed that on resonance frequency real parts of permittivity and permeability of such media can assume simultaneously negative values. The problem of reflection and transmission of plane electromagnetic wave through a sequence of layers made of such composite material is solved, numerical results are presented
8. Al_{0,3}Ga_{0,7}As/GaAs cathode transfer electron diode's efficiency O.V. Botsula Prokhorov E.D, A.V. Dydchenko doping, cathode contact, tunnelling, negative differential conductivity, oscillation efficiency Vestnik KhNU ¹756 Pages. 97100
The results of analyse efficiency of GaAs/ Al0,3Ga0,7As/GaAs GaAs/ Al0,3Ga0,7As/GaAs / GaAs cathode transfer electron diode are present. The space charge model are used. There are two region of negative differential conductivity of current  voltage characteristic are shown . The condition lead to oscillation due both region and oscillation efficiency have been determined.
9. Wide range mmwave GAAS oscillator with electronic frequency gliding A.V. Dyadchenko, E.D. Prokhorov oscillators, electronic frequency gliding, oscillating efficiency Vestnik KhNU ¹756 Pages. 101104
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
10. AlN/AlxGa1_{x}N resonance tunnell diodes D.V. Pavlenko, E.D. Prokhorov nitrides, quantum well, NDC, oscillation efficiency. Vestnik KhNU ¹756 Pages. 105108
Double and threefold compounds of nitrides AIN/AIGaN resonance tunnel diodes using height of barriers are concedered. In the quantum well of diodes there are a plenty energy levels. Electron energy levels in quantum well with variable structure of interconnections AlGaN are determined. The current  voltage characteristics of resonance  tunnel diodes with number of levels in a quantum wall up to five has been calculated. The RTD can have up to five sites with negative differential conductance are demonstrated. The possible RTD oscillation efficiency on all sites of negative differential conductivity at difference barriers and quantum well's material are determined.
11. Influence of impact ionization on efficiency of rscadiodes operation on basis of InN, GaN, AIN D.V. Pavlenko, E.D. Prokhorov nitrides, RSCA oscillators, oscillating efficiency, drift velocity Vestnik KhNU ¹756 Pages. 109112
The impact ionisation in RSCA diodes is considered on the basis of nitrides InN, GaN, AIN. Possible overvoltage on diodes and possible efficiency of generation are analyzed. It is shown, that at development of a impact ionisation in RSCA diodes in correspondence with the diffusion theory the considered materials are perspective for RSCA diodes for operation in centimeter and millimeter wavebands (voltage over threshold 3 ... 5 at efficiency up to 11 ... 13 %)
12. Amplitude and noise features of detectors a mm of range of lengths of waves on base of contacts a metalsemimetal BiSb O.N. Sukhoruchko, V.T. Plaksiy, E.D. Prokhorov, A.V. Dyadchenko contact metalsemimetal BiSb, power zones, contact a metaisemimetal BiSb, millimeter range of lengths of waves, relative noise temperature, influence of displacing and resistances of contacts on sensitivity Vestnik KhNU ¹756 Pages. 113117
In work are brought results of analytical and experimental thermoelectrical detector study with the point contact a metalsemimetal BiSb. Determined relative noise temperature, as well as influence of displacing and resistances of contacts on the sensitivity in 8 mm range of waves.
13. THE H_{10} WAVE SCATTARING BY THE THIN VARIABLE RADIUS IMPEDANCE VIBRATOR IN A Nesterenko, E.Y. Belogurov, V.A. Katrich, V.I Kijko impedance vibrator, biconical vibrator, distributed surface impedance, rectangular waveguide, the method of induced electromotive forces Vestnik KhNU ¹806 Pages. 1417
The problem of the fundamental wave scattering by the thin variable radius impedance vibrator arbitrary situated in a rectangular waveguide was solved. Calculations were carried out and energetic characteristics of such structures were plotted
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14. CALCULATION AND MEASURING OF IMPEDANCE OF IMPATTDIODE IN MILLIMETR WAVE A.V. Arkhipov, V.T. Plaksiy, I.K. Kuzmichev, E.D. Prokhorov, A.V. Dydchenko, D.P. Chuechkov millimeter wave range, impedance, IMPATT diode, conductance, susceptance Vestnik KhNU ¹806 Pages. 5964
The calculated and experimental results of the impedance of the impact avalanche transittime (IMPATT) diode for the 8 millimeter wavelength range have been presented. The dependences of the IMPATT diode impedance as a function of the normalized amplitude î Ã the fundamental current harmonic of the pn junction and frequency have been calculated and measured. The apparatus and measuring method of the conductance and susceptance of the IMPATT diode has been developed
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15. HARMONIC GENERATION BY IMPACT IONIZATION IN CaN LSA DIOD O.V. Botsula, D.V. Pavlenko, E.D. Prokhorov LSA diodes, generation efficiency, nitrides, drift velocity, harmonics Vestnik KhNU ¹806 Pages. 6569
In this work an impact ionization in LSA diodes on basis of GaN is considered. Analytical calculation of typical times of passing of a number of the physical processes determining properties of the oscillator, and limitings imposed by them on frequency properties of the diode is submitted. It is shown, that at developing impact ionization in LSA diodes, according to the diffusive theory, the considered compounds are perspective for manufacturing LSA diodes for work in sm and mm  ranges (electrical pressure over threshold 3 … 5 times, at an efficiency up to 11 … 13 %). The results of calculation of efficiency of oscillators on basis of GaN LSA diodes are given at their work in modes on a base frequency and at a harmonic generation.
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16. Theory of the millimeter waves otype clinotron amplifier E.N. Odarenko, A.A. Shmat'ko nonlinear multidimensional theory, clinotron amplifier, electrons settling Vestnik KhNU ¹806 Pages. 7581
Nonresonant amplifier Otype system with inclined focusing field is considered. Theoretical investigation is carried out within the framework of the beamwave 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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17. Subterahertz diffraction radiation on the BWO frequency harmonics in the parametrical tworegimes electron device E.N.Odarenko, A.A.Shmat’ko, P.V. Yudintcev diffraction radiation, SmithPurcell effect, subterahertz waves, beamwave interaction, nonlinear processes Vestnik KhNU ¹834 Pages. 1317
Diffraction radiation nonlinear theory that takes into account tworegimes interaction – selfconsistent regimes of the BWO and GDI on the BWO frequency harmonics is developed. The existence of the BWO generation regime on the first harmonic and parametric type diffraction radiation amplification regime on the BWO frequency harmonics is shown on the base of the selfconsistent equations set numerical solution. Ranges of the task parameters values that correspond to tworegimes interaction are defined
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18. Farfield distance of waveguide radiators N.N. Gorobets, E.E. Ovsyannikova, A.V. Shishkova rectangular waveguide, microwaves, boundary of far zone, amplitude, phase radiation characteristics Vestnik KhNU ¹834 Pages. 6876
On the basis of Hertz potentials in Kirchhoff approximation the amplitude and phase radiation characteristics of openended rectangular waveguide excited by TE_{10} dominant mode are investigated at arbitrary distance from radiating aperture. The estimation criteria of far zone boundary for small (in comparison with the wavelength) waveguide radiators are presented. For such small radiators, the classic formula for calculation of farfield distance cannot be applied. Under suggested criteria the investigation of radiation characteristics are carried out. For waveguides with the sizes less then the wavelength in the waveguide, the boundaries of farfield distance are defined
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19. Frequency multiplication at impact ionization in GaNdiodes Î. V. Botsula, D. V. Pavlenko, E. D. Prokhorov the GaN diode, coefficient conversion transducing, drift velocity, harmonics Vestnik KhNU ¹834 Pages. 100103
The frequency multiplication at impact ionization in transfer electron GaN diodes nave been considered. The coefficient conversion transducing increase if impact ionization in GaN diodes takes place have been demonstrated. For example, coefficient conversion transducing in second harmonic arrive at 40 %.
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20. Cathode static domen in transfer electron devise Î. V. Botsula, D.V. Pavlenko, E.D. Prokhorov static domen, velocity – field characteristic, electric field strange Vestnik KhNU ¹834 Pages. 104107
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 êÂ/sm (for gomogenues velosity – field characteristic in ower dides) have been derermened
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21. Potentially unbreacable ciphering on a hybrid physicalmathematical level A. G. Tyzhnenko, E. V. Ryeznik bit, stochastic signals, safe communication, hard drive protection Vestnik KhNU ¹834 Pages. 108113
A new kind of ciphering based on stochastic representation of bits as series of samples is addressed. Stochastic comparison is used for bit identification. Security level is increased by adding noise samples to signal samples and mixing signal samples with noise samples within one signal packet. The signal packet length and distribution features of signal samples among noise samples in signal packets are unique for given communication line, as well as stochastic representation of bits (0s and 1s). Using of noise in signal packets leads to enormous large computation in decrypting process which is unrealistically to do regardless what computer system is used. More to the point, the unique features of communication line mentioned above can be changed for each message that prevents information leakage in the case of stealing these ones in any previous period. Impossibility of decrypting by any reasonable time period of any message eavesdropped by a cryptanalyst guarantees the confidence of information which has permanent importance
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22. 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 ¹834 Pages. 114119
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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23. Capacitancevoltage measurements in selectively doped ALGAAS/GAAS heterostructures N.B.Gorev, I.F. Kodzhespirova, E.N. Privalov gallium arsenide, selectively doped heterostructures, Schottky barrier, barrier capacitance, capacitance–voltage measurements Vestnik KhNU ¹853 Pages. 37
The dependence of the measured apparent capacitance of selectively doped AlGaAs/GaAs heterostructures on the amplitude of the measuring ac voltage is calculated numerically. An expression that gives the measured apparent capacitance as a function of the true capacitance and the above amplitude is derived. Using this expression and the results of the above numerical calculation, it is shown that capacitance–voltage characteristics of selectively doped AlGaAs/GaAs heterostructures, which feature steeply dropping regions, may be measured at moderately small amplitudes of the measuring ac voltage (of the order of 100 mV) at the expense of taking measurements at two different amplitudes
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24. Oscillation efficiency of TED diodes on the basis of nitrides E. D. Prokhorov, O. V. Botsula, A. N. Zabazhan AlN, GaN, InNdiodes, drift speed, oscillation efficiency Vestnik KhNU ¹853 Pages. 1521
Oscillation efficiency of intervalley transfer electrons diodes on the basis of nitrides (InN, GaN, AlN) is considered. Electric fields at peak oscillation efficiency are determined. The results have been compared to results for GaAs. The account of floatable potential in connections InGaN improves their power characteristics in comparison with power characteristics of these connections without taking into account floatable potential, maximal efficiency In_{0.8 }Ga _{0.2N and In0.5Ga0.5N diodes to compare to InN diodes on 30 % is higher (22 % to compare to 16,43 %) but at more high tensions of an electric field. The maximal oscillation efficiency is observed at higher electric fields than GaAs ( from 250 êV/sm for InN to 1000 kV/sm for AlN)}
25. Influence of apertureillumination law on nearfield characteristics of aperture antennas E.E. Ovsyannikova, A.V. Shishkova, N.N. Gorobets electromagnetic waves, reactive fields, aperture radiators, Kirchhoff technique, nearfield, farfield, amplitude distributions, phase characteristics, amplitude characteristics, reactive radiation power Vestnik KhNU ¹853 Pages. 2836
On the basis of Hertz potentials the investigation of nearfield 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 nearfield region have been carried out. The analysis of the criteria for estimation of nearfield reactive region boundary has been carried out
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26. FREQUENCY MULTIPLICATION AT IMPUCT IONIZATION IN TRASFER ELECTRON DIODES ON BASIS AlN, InN E. D. Prokhorov, O.V. Botsula, I. A. Grishchenko AlN, GaN, InN diodes, frequency transformation factor , drift velocity, harmonics. Vestnik KhNU ¹883 Pages. 3034
Multiplication of frequency at impact ionization in intervalley transfer electron diodes on basis InN, AlN is considered. The current – voltage characteristics of intervalley transfer electron diodes have negative conductivity region and strong increasing
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27. NonstationarY processes in the hybrid Otype beamwave system Odarenko E.N., Shmatko A.A. nonautonomous oscillatory system, locking, beats Vestnik KhNU ¹966 Pages. 2330
Nonstationary processes in the resonant beamwave system with premodulated electron beam are investigated in this work. Theoretical analysis is performed on the basis of the nonlinear multidimensional theory of the hybrid Otype electron devices. Basic regularities of the external signal power effect on the lock range width are described. Regimes of the oscillations synchronization, beats and squitter for different values of the oscillation system and external signal parameters are considered.
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28. Impedance characteristics of planar diodes with tunnel boundaries based on GaAs Prokhorov E.D., Botsula O.V., Klimenko O.A. : negative differential conductivity, tunnel boundary, a diode, the tunneling. Vestnik KhNU ¹966 Pages. 1318
The impedance characteristics of the diodes are consider, which negative differential conductivity (NDC) is arise under certain voltage, due to tunneling of electrons through the side faces of the diode, which can be used for generation, amplification and multiplication. Depending on the active and reactive components of impedance are determined of the diode with the tunnel boundaries for the real parameters of the diodes. It is shown that the limiting frequency of the diode NDC is in the terahertz range and depends on its parameters.
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29. Determena Frequency properties of intervalley electron transfer in AlN V. T. Plaksiy, À.V.Arhipov, À. S. Tischenko, Ò. ². Kamishanova, E.D. Prokhorov, À.V.Dyadchenko, D. P.Chueshkov perfect crystal, zone overcrystallization, temperature gradient Vestnik KhNU ¹966 Pages. 1922
The problem of growing of perfect bismuthantimony monocrystals having of a uniform distribution of Sb atoms through the crystal by help floatingzone refining method is considered. The expression for temperature gradient in melt and temperature distribution for any melt point have been obtained.
The monocrystals growing maximal velocity have been estimated. The growing velocity must be lower then 1 mm per hour was showed. It is velocity not lead to concentration overcooling and arising inhomogeneous dendrite structure. For solution with certain composition ( at = const) overcooling may be eliminated by either increasing of temperature gradient in liquid faze or decreasing growing velocity are showed.
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