The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform

V. I. Shcheglov - One of the best experts on this subject based on the ideXlab platform.

  • Dispersion of magnetostatic waves in the tangentially magnetized Ferrite Plate with the anisotropy axis perpendicular to its plane
    Journal of Communications Technology and Electronics, 2020
    Co-Authors: V. I. Zubkov, V. I. Shcheglov
    Abstract:

    The law of dispersion of magnetostatic waves (MSWs) in the tangentially magnetized Ferrite Plate (FP) with the uniaxial anisotropy, whose axis is perpendicular to its plane, is obtained and analyzed in the case when the applied constant magnetic field is less than the uniaxial anisotropy field. It is shown that this model qualitatively describes the MSW dispersion in hexa- and ortho-Ferrites and also in a nonsaturated FP.

  • Ferromagnetic resonance in a tangentially magnetized Ferrite Plate with normal uniaxial anisotropy and domain structure
    Journal of Communications Technology and Electronics, 2020
    Co-Authors: V. I. Zubkov, V. I. Shcheglov
    Abstract:

    A theoretical model is developed for the ferromagnetic resonance in a tangentially magnetized Ferrite Plate with normal uniaxial anisotropy and domain structure. The model is based on the allowance for local effective fields (demagnetization fields induced by ends and lateral faces of domains and fields caused by the interaction of domain magnetizations through the ends and lateral faces). It is shown that the spectrum of the ferromagnetic resonance consists of two (as a rule, degenerate) branches. The degeneration of the spectrum branches disappears only when the interaction of domain magnetizations through the domain ends is taken into account. Comparison of the proposed model with experimental data revealed that the ferromagnetic-resonance spectrum contains a frequency gap, whose parameters depend on the external magnetic field. This gap is of fundamental importance for materials with large magnetization and small uniaxial anisotropy.

  • Multiplicative Frequency Conversion in a Scheme of Magnetostrictive Transducer. Frequency Multiplication in the Relaxation Regime
    Journal of Communications Technology and Electronics, 2019
    Co-Authors: Vladimir G. Shavrov, V. I. Shcheglov
    Abstract:

    Stimulated oscillations of magnetization and elastic displacement in a normally magnetized Ferrite Plate with magnetoelastic properties are considered. Frequency multiplication at the ratio determined by the multiplicity of the resonance frequencies of the magnetic and elastic subsystems is analyzed. Time and amplitude characteristics of the effect are studied using a model of the impact excitation of the elastic system due to short-term effect of the magnetic system. Frequency division in the same scheme of the magnetostrictive transducer is employed for comparison.

  • Application of the model of coupled oscillators in the analysis of the nonlinear excitation of hypersound in a Ferrite Plate under ferromagnetic resonance. Part 2. Nonlinear effects
    Journal of Communications Technology and Electronics, 2015
    Co-Authors: V S Vlasov, Vladimir G. Shavrov, A. P. Ivanov, V. I. Shcheglov
    Abstract:

    The excitation of hypersonic oscillations by ac magnetic field is considered in the framework of the problem of the magnetostriction microwave transducer using a model of coupled oscillators. Two regimes of the development of forced oscillations corresponding to an increase and decrease in the amplitude in time are separated by a bifurcation point. Two criteria of bifurcation are proposed to determine the critical values of the coupling constant and resonance frequency. The bifurcation point between the regimes is equivalent to the point of reorientation of the magnetization vector. It is demonstrated that the cubic nonlinearity plays the main role in the limitation of the exponential growth of the amplitude of forced oscillations. Frequency response functions (FRFs) of the coupled oscillations are considered at several excitation levels. It is demonstrated that the quadratic approximation provides the analysis of FRF with respect to magnetic oscillations with an accuracy of no worse than 2% if the ac-field amplitude is no greater than 0.7 of the saturation magnetization. The applicability of the quadratic approximation in the analysis of the self-sustained self-modulation process is considered. It is demonstrated that the model system fully characterizes the development of envelopes of both regular and chaotic self-modulation oscillations and the amplitude difference relative to the solution to the complete system is no greater than 20%. The calculations based on the model of coupled oscillators in the quadratic approximation allow a two-fold decrease in the computer resources and a decrease in the computation time by two orders of magnitude.

  • Magnetostatic waves in a tangentially magnetized Ferrite Plate with a normal uniaxial anisotropy under the conditions for orientational transition
    Journal of Communications Technology and Electronics, 2012
    Co-Authors: V. I. Zubkov, V. I. Shcheglov
    Abstract:

    Propagation of magnetostatic waves in a tangentially magnetized Ferrite Plate with a normal uniaxial anisotropy under the conditions for the orientational phase transition of the second order is considered. Dispersion relations for quasi-surface and quasi-volume magnetostatic waves with the wave vector arbitrarily oriented in the plane of the Plate have been obtained. The limiting frequencies of the regions of existence of both modes have been determined and the dependences of these frequencies on the anisotropy field and wave-vector orientation have been investigated.

M. Itoh - One of the best experts on this subject based on the ideXlab platform.

  • Experimental Research on Improvement of the Orientation Characteristics of a Slit Ferrite Plate in the RF Magnetic Field: Superposition of a Slit Carbon Plate Over a Slit Ferrite Plate
    IEEE Transactions on Applied Superconductivity, 2010
    Co-Authors: T. Nishikubo, H. Endo, M. Itoh
    Abstract:

    As part of the basic research for the improvement of the electromagnetic environment, the present study has developed a Ferrite Plate having orientation characteristics. To exhibit the orientation characteristics of a plane wave, a slit was cut on the surface of the Ferrite Plate. The values of the radio frequency (RF) magnetic shielding degree SDHH when holding the slit horizontal to the ground, in the frequency region of 1 MHz (43 dB) to 200 MHz (8 dB), decreased with frequency. The value of RF magnetic shielding degree SDHP when holding the slit perpendicular indicated an average value of 20 dB in this frequency region. Namely, the values of the difference, SDHH - SDHP, indicated an average value of 13 dB as the orientation characteristics. The orientation characteristics of the Ferrite Plate, however, displayed no orientation characteristics in the frequency region of 200 MHz to 3 GHz. Therefore, in order to improve the orientation characteristics in this frequency region, a compound Plate was formed by the superposition of a slit carbon Plate over the slit Ferrite Plate. The values of the difference, SDHH - SDHP, for the compound Plate were then improved by approximately 35 dB in the frequency region from 1 MHz to 3 GHz. Experimental results revealed several orientation characteristics of the compound, slit Ferrite and carbon Plates.

  • Manufacture of an RF Magnetic Shielding Plate Having Orientation Characteristics
    IEEE Transactions on Instrumentation and Measurement, 2009
    Co-Authors: T. Nishikubo, H. Endo, M. Itoh
    Abstract:

    As one of the basic areas of research for the improvement of the electromagnetic environment, this paper has developed a carbon Plate having orientation characteristics. To exhibit the orientation characteristics in a plane wave, a slit was cut on the surface of a carbon Plate. The value of the radio frequency (RF) magnetic shielding degree SD HP when holding the slit in the carbon Plate perpendicularly, in the frequency region from 1 MHz to 1 GHz, increased with frequency and had a value of 48 dB at 1 GHz. It was also shown that the value of SD HH when holding the slit horizontally indicated about 15 dB in the frequency region from 1 MHz to 1 GHz. Namely, the difference in the values of shielding degree of the carbon Plate versus the orientation of slit indicated the characteristics of the orientation. Experimental results revealed several characteristics of the slit carbon Plate that include the influences of the slit length L, slit number N, and slit width w on the characteristics of the orientation. In this paper, the orientation characteristics were improved by the superposition of a slit Ferrite Plate over a slit carbon Plate, termed the compound Plate. In addition, important criteria are discussed for the design of a Plate for effective RF magnetic shielding having orientation characteristics.

  • Fabrication of RF Magnetic Shielding Plate Having the Polarization Characteristics
    2007 IEEE Instrumentation & Measurement Technology Conference IMTC 2007, 2007
    Co-Authors: T. Nishikubo, H. Endo, H. Norikane, K. Itoh, Fumio Tojo, M. Itoh
    Abstract:

    As one of the basic areas of research for the improvement of the electromagnetic environment, the present paper has developed the carbon Plate having the polarization characteristics. To exhibit the polarization characteristics in the far field region, it has formed the slit on the surface of carbon Plate. The value of the RF magnetic shielding degree SDHH for holding the slit of a carbon Plate horizontally, in the frequency region of 1 MHz to 1 GHz, increased with frequency, and had the value of 58 dB at 1 GHz. Also shown that the value of SDHP for holding the slit perpendicularly indicated about 10 dB in the frequency region of 1 MHz to 1 GHz. Namely, the difference of shielding degrees of the carbon Plate to direction of slit is indicated the polarization characteristics. Experimental results revealed several characteristics of the slitting carbon Plate that include the influences of polarization characteristics on the slit length L and slit number N. In the present paper, it is improved the polarization characteristics by the superposition of slitting Ferrite Plate over a slitting carbon Plate, termed a compound Plate. In addition, important criteria are discussed for the design of an effective RF magnetic shielding Plate having polarization characteristics.

  • RF Magnetic Shielding Effects of a Compound Plate Constructed From Bincho-Charcoal and Ferrite Plates
    IEEE Transactions on Applied Superconductivity, 2006
    Co-Authors: H. Norikane, T. Nishikubo, S. Gokyu, K. Itoh, M. Itoh
    Abstract:

    With rapid development in the field of information technology, there has been increased interest for electromagnetic shielding in the radio frequency (RF) region. An excellent RF magnetic shielding material can be realized by the use of bincho-charcoal, a high quality charcoal found in Japan, due to its very large value of relative permittivity in the RF region. The present paper has improved the RF magnetic shielding characteristics of a bincho-charcoal Plate to realize a broadband frequency by the superposition of a Ferrite Plate over the bincho-charcoal Plate. This configuration is termed the compound Plate. The RF magnetic shielding effects of the compound Plate have been examined, including the characteristics of the RF magnetic effect against both the frequency and the RF magnetic power. In addition, RF electric shielding effects have been examined as functions of the frequency and the RF electric power

V. I. Zubkov - One of the best experts on this subject based on the ideXlab platform.

G. A. Kraftmakher - One of the best experts on this subject based on the ideXlab platform.

  • New Functional Capabilities of Microwave Interferometry When Using Metastructure as a Tunable Beam Splitter
    Journal of Communications Technology and Electronics, 2019
    Co-Authors: G. A. Kraftmakher, V. S. Butylkin, Yu. N. Kazantsev, V. P. Mal’tsev
    Abstract:

    — It is experimentally shown that the microwave metainterferometer with a metastructure (metasurface or metaatom) as a tunable beam splitter possesses the unique possibility to specify selective magnetic and electric tuning of multiband filtration of electromagnetic waves. The investigation results are shown concerning the interferogram of a modified metainterferometer based upon the waveguide tee junctions in which the metastructure contains a Ferrite Plate or a structure made of conducting resonant elements compatible with the controlling elements or their combination with Ferrite. The dependences of the shape, width, intensity, and frequency of the interference band on the value and sign of a magnetostatic field, on the relative position of ferromagnetic resonance and the band, and on the electric voltage on the varactors included in the discontinuities of elements. We have experimental results that open new methods and approaches in the design of switchable and tunable multiband microwave filters needed in multifunctional multichannel telecommunication systems.

  • Magnetically and Electrically Controlled Microwave Interference Pattern in a Meta-Interferometer
    JETP Letters, 2019
    Co-Authors: G. A. Kraftmakher, V. S. Butylkin, Yu. N. Kazantsev, V. P. Mal’tsev
    Abstract:

    A specific selective effect of ferromagnetic and dipole resonances on an interference pattern in the range of 3–6 GHz has been detected experimentally for the first time in a modified interferometer based on a waveguide T junction with a metastructure consisting of a Ferrite Plate and varactor-loaded dipole or ring conducting elements as a controlled beam splitter. A dependence of the shape, width, intensity, and frequency of an interference band on the magnitude and sign of a static magnetic field H , the relative position of ferromagnetic resonance and band, and the electric voltage V _DC on varactor diodes has been observed. The nonreciprocity of microwave transmission in interference stop bands characterized by change in the transmission coefficient T at the inversion of H has been revealed. Nonreciprocity increases at the excitation of ferromagnetic resonance near a band. In this case, a jump of T by two orders of magnitude to a level of a passband is observed with the reversal of the magnetic field H . The sign of nonreciprocity depends on the relative position of ferromagnetic resonance and the stop band and can change at a small variation of the magnitude of H . The selectively controlled narrowing of the nonreciprocal band by several times, as well as the shift by 0.2 GHz, is observed with the variation of V _DC in the range of 0–10 V.

  • Metasandwich Ferrite Plate/wire grating/longitudinal copper strip with varactor to achieving controlled microwave nonreciprocal absorption
    2017 Progress In Electromagnetics Research Symposium - Spring (PIERS), 2017
    Co-Authors: G. A. Kraftmakher, V. S. Butylkin, Yu. N. Kazantsev, V. P. Mal'tsev
    Abstract:

    Three-layer metasandwich Ferrite Plate/periodical wire grating/varactor-loaded orthogonal asymmetric strip is proposed, realized and investigated experimentally in rectangular waveguide at microwaves. It has been shown that metasandwich possesses electrically/magnetically controlled nonreciprocal microwave resonant absorbing of linearly polarized magnetic field of incident wave and not strong forward losses under multi-coupled resonances.

  • Electrically controlled nonreciprocity inversion of microwave transmission in a metastructure based on Ferrite and a varactor-loaded dipole
    Technical Physics Letters, 2015
    Co-Authors: G. A. Kraftmakher, V. S. Butylkin, Yu. N. Kazantsev
    Abstract:

    A possibility of electrical control of nonreciprocity inversion of microwave propagation when using a metastructure with a Ferrite Plate and varactor-loaded dipole is demonstrated. In contrast to conven-tional methods, the inversion occurs without Ferrite remagnetization. It is reached by varying the constant bias voltage on varactor that enables the tuning of the resonance frequency of dipole to the frequency of ferromagnetic resonance. This effect occurs due to the fact that a magnetic field with elliptical polarization is formed near a dipole as a result of superposition of incident and scattered waves, rotating in one direction below the resonance frequency of dipole and in the opposite direction above the frequency of this resonance.

  • Electrically controlled frequency bands of nonreciprocal passage of microwaves in metastructures
    Technical Physics Letters, 2013
    Co-Authors: G. A. Kraftmakher, V. S. Butylkin, Yu. N. Kazantsev
    Abstract:

    Measurements of the transmission coefficients of linearly polarized waves in a rectangular waveguide along a metastructure formed by a transversely magnetized Ferrite Plate and double-split rings with varactors indicated the presence—in addition to the ferromagnetic resonance—of a resonance region of nonreciprocal passage, which is controlled, in contrast to the ferromagnetic resonance, by the electric field. This effect manifests itself in magnetic fields substantially lower than the field exciting the ferromagnetic resonance at these frequencies. Electrically controlled nonreciprocal passage of microwaves cannot be achieved by means of known natural materials or traditional ferromagnets.

T. Nishikubo - One of the best experts on this subject based on the ideXlab platform.

  • Experimental Research on Improvement of the Orientation Characteristics of a Slit Ferrite Plate in the RF Magnetic Field: Superposition of a Slit Carbon Plate Over a Slit Ferrite Plate
    IEEE Transactions on Applied Superconductivity, 2010
    Co-Authors: T. Nishikubo, H. Endo, M. Itoh
    Abstract:

    As part of the basic research for the improvement of the electromagnetic environment, the present study has developed a Ferrite Plate having orientation characteristics. To exhibit the orientation characteristics of a plane wave, a slit was cut on the surface of the Ferrite Plate. The values of the radio frequency (RF) magnetic shielding degree SDHH when holding the slit horizontal to the ground, in the frequency region of 1 MHz (43 dB) to 200 MHz (8 dB), decreased with frequency. The value of RF magnetic shielding degree SDHP when holding the slit perpendicular indicated an average value of 20 dB in this frequency region. Namely, the values of the difference, SDHH - SDHP, indicated an average value of 13 dB as the orientation characteristics. The orientation characteristics of the Ferrite Plate, however, displayed no orientation characteristics in the frequency region of 200 MHz to 3 GHz. Therefore, in order to improve the orientation characteristics in this frequency region, a compound Plate was formed by the superposition of a slit carbon Plate over the slit Ferrite Plate. The values of the difference, SDHH - SDHP, for the compound Plate were then improved by approximately 35 dB in the frequency region from 1 MHz to 3 GHz. Experimental results revealed several orientation characteristics of the compound, slit Ferrite and carbon Plates.

  • Manufacture of an RF Magnetic Shielding Plate Having Orientation Characteristics
    IEEE Transactions on Instrumentation and Measurement, 2009
    Co-Authors: T. Nishikubo, H. Endo, M. Itoh
    Abstract:

    As one of the basic areas of research for the improvement of the electromagnetic environment, this paper has developed a carbon Plate having orientation characteristics. To exhibit the orientation characteristics in a plane wave, a slit was cut on the surface of a carbon Plate. The value of the radio frequency (RF) magnetic shielding degree SD HP when holding the slit in the carbon Plate perpendicularly, in the frequency region from 1 MHz to 1 GHz, increased with frequency and had a value of 48 dB at 1 GHz. It was also shown that the value of SD HH when holding the slit horizontally indicated about 15 dB in the frequency region from 1 MHz to 1 GHz. Namely, the difference in the values of shielding degree of the carbon Plate versus the orientation of slit indicated the characteristics of the orientation. Experimental results revealed several characteristics of the slit carbon Plate that include the influences of the slit length L, slit number N, and slit width w on the characteristics of the orientation. In this paper, the orientation characteristics were improved by the superposition of a slit Ferrite Plate over a slit carbon Plate, termed the compound Plate. In addition, important criteria are discussed for the design of a Plate for effective RF magnetic shielding having orientation characteristics.

  • Fabrication of RF Magnetic Shielding Plate Having the Polarization Characteristics
    2007 IEEE Instrumentation & Measurement Technology Conference IMTC 2007, 2007
    Co-Authors: T. Nishikubo, H. Endo, H. Norikane, K. Itoh, Fumio Tojo, M. Itoh
    Abstract:

    As one of the basic areas of research for the improvement of the electromagnetic environment, the present paper has developed the carbon Plate having the polarization characteristics. To exhibit the polarization characteristics in the far field region, it has formed the slit on the surface of carbon Plate. The value of the RF magnetic shielding degree SDHH for holding the slit of a carbon Plate horizontally, in the frequency region of 1 MHz to 1 GHz, increased with frequency, and had the value of 58 dB at 1 GHz. Also shown that the value of SDHP for holding the slit perpendicularly indicated about 10 dB in the frequency region of 1 MHz to 1 GHz. Namely, the difference of shielding degrees of the carbon Plate to direction of slit is indicated the polarization characteristics. Experimental results revealed several characteristics of the slitting carbon Plate that include the influences of polarization characteristics on the slit length L and slit number N. In the present paper, it is improved the polarization characteristics by the superposition of slitting Ferrite Plate over a slitting carbon Plate, termed a compound Plate. In addition, important criteria are discussed for the design of an effective RF magnetic shielding Plate having polarization characteristics.

  • RF Magnetic Shielding Effects of a Compound Plate Constructed From Bincho-Charcoal and Ferrite Plates
    IEEE Transactions on Applied Superconductivity, 2006
    Co-Authors: H. Norikane, T. Nishikubo, S. Gokyu, K. Itoh, M. Itoh
    Abstract:

    With rapid development in the field of information technology, there has been increased interest for electromagnetic shielding in the radio frequency (RF) region. An excellent RF magnetic shielding material can be realized by the use of bincho-charcoal, a high quality charcoal found in Japan, due to its very large value of relative permittivity in the RF region. The present paper has improved the RF magnetic shielding characteristics of a bincho-charcoal Plate to realize a broadband frequency by the superposition of a Ferrite Plate over the bincho-charcoal Plate. This configuration is termed the compound Plate. The RF magnetic shielding effects of the compound Plate have been examined, including the characteristics of the RF magnetic effect against both the frequency and the RF magnetic power. In addition, RF electric shielding effects have been examined as functions of the frequency and the RF electric power