Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003002
Sergei Gerus, E. Lock
Purpose of this paper is to give an overview of various experimental methods for investigation of spin waves characteristics. Methods. The paper presents a description of a number of experimental techniques, such as the probing method, the phase shift method, the method of measure of equiphase dependences, the method of intersecting wave beams, and the use of Fourier analysis of the complex transfer coefficient of spin waves to determine their spatial spectrum. The conditions for using the listed methods and the characteristics of spin waves that one can measure by means of these methods are discussed in detail. Results. The paper presents a number of fundamental results that have been obtained on the basis of described methods. For example, the probing method was successfully used to visualize the amplitude and phase distribution of spin waves in the ferrite film plane and, in particular, it was used to experimentally confirm the previously predicted appearance of super-directed propagation of surface and backward volume spin wave beams. The phase-shift measurement method made it possible to measure the dispersion dependence of spin waves in ferrite structures such as ferrite – metal and ferrite – dielectric – metal, where measurements cannot be made by the probing method. The method of measuring equiphase dependences of spin waves made it possible, in particular, to measure for the first time with great accuracy the value of an external magnetic field magnetizing an yttrium iron garnet film to saturation in various crystallographic directions. The method of intersecting wave beams has made it possible to clarify the mechanism of parametric instability of surface spin waves. Fourier analysis of the complex transfer coefficient of spin waves allowed to determine the spatial spectrum of these waves; in particular, dispersion dependences of higher modes of the backward volume spin wave were first measured using this method. Conclusion. The methods described in this paper may continue to be successfully used for investigations of spin waves characteristics in various magnon crystals, ferrite structures and meta-structures.
{"title":"Experimental methods for the study of spin waves","authors":"Sergei Gerus, E. Lock","doi":"10.18500/0869-6632-003002","DOIUrl":"https://doi.org/10.18500/0869-6632-003002","url":null,"abstract":"Purpose of this paper is to give an overview of various experimental methods for investigation of spin waves characteristics. Methods. The paper presents a description of a number of experimental techniques, such as the probing method, the phase shift method, the method of measure of equiphase dependences, the method of intersecting wave beams, and the use of Fourier analysis of the complex transfer coefficient of spin waves to determine their spatial spectrum. The conditions for using the listed methods and the characteristics of spin waves that one can measure by means of these methods are discussed in detail. Results. The paper presents a number of fundamental results that have been obtained on the basis of described methods. For example, the probing method was successfully used to visualize the amplitude and phase distribution of spin waves in the ferrite film plane and, in particular, it was used to experimentally confirm the previously predicted appearance of super-directed propagation of surface and backward volume spin wave beams. The phase-shift measurement method made it possible to measure the dispersion dependence of spin waves in ferrite structures such as ferrite – metal and ferrite – dielectric – metal, where measurements cannot be made by the probing method. The method of measuring equiphase dependences of spin waves made it possible, in particular, to measure for the first time with great accuracy the value of an external magnetic field magnetizing an yttrium iron garnet film to saturation in various crystallographic directions. The method of intersecting wave beams has made it possible to clarify the mechanism of parametric instability of surface spin waves. Fourier analysis of the complex transfer coefficient of spin waves allowed to determine the spatial spectrum of these waves; in particular, dispersion dependences of higher modes of the backward volume spin wave were first measured using this method. Conclusion. The methods described in this paper may continue to be successfully used for investigations of spin waves characteristics in various magnon crystals, ferrite structures and meta-structures.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79881796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003004
D. Burdin, D. Chashin, N. Ekonomov, Y. Fetisov
The effect of a giant change in the impedance of ferromagnetic materials under the action of an external magnetic field is widely used to elaborate highly sensitive magnetic field sensors. The purpose of this work was to demonstrate the possibilities of controlling the magnitude of the magnetoimpedance in a ferromagnet-piezoelectric structure using an electric field. Method. In the measurements, we used a planar heterostructure containing a strip of amorphous ferromagnet Metglas, 25 µm thick and 25 mm long, mechanically connected to a bimorph, 0.5 mm thick and 30 mm long, made of piezoceramic lead zirconate titanate. An alternating current with a frequency of 30 kHz...10 MHz was passed through the strip, the structure was placed in a longitudinal permanent magnetic field of 0...500 Oe, an alternating electric field up to 400 V/cm with a frequency of 60 Hz...50 kHz was applied to the piezobimorph, and the change in the impedance of the strip was recorded. Results. In the absence of electric field, a narrowing of the magnetoimpedance magnetic fields region with a decrease in the current frequency and saturation of the magnetoimpedance in magnetic fields above 334 Oe were observed. The maximum value of the magnetoimpedance reached 18% at a current frequency of 1 MHz. The application of electric field to the piezobimorph led to the appearance of side components in the frequency spectrum of the voltage on the ferromagnetic layer, which indicates the amplitude-phase modulation of the magnetoimpedance. The amplitude modulation coefficient reached a maximum value of 6 · 10−3 for the electric field frequency of 11.2 kHz and decreased monotonically with an increase in the magnetic field. The modulation of the magnetoimpedance occurs due to the converse magnetoelectric effect in the heterostructure, which leads to the modulation of the magnetization of the ferromagnetic layer, and the subsequent change in the relative magnetic permeability and thickness of the skin layer in the ferromagnet. The results obtained can be used to create magnetic fields sensors controlled by an electric field.
{"title":"Magnetoimpedance modulation in a planar magnetoelectric ferromagnet – piezoelectric heterostructure","authors":"D. Burdin, D. Chashin, N. Ekonomov, Y. Fetisov","doi":"10.18500/0869-6632-003004","DOIUrl":"https://doi.org/10.18500/0869-6632-003004","url":null,"abstract":"The effect of a giant change in the impedance of ferromagnetic materials under the action of an external magnetic field is widely used to elaborate highly sensitive magnetic field sensors. The purpose of this work was to demonstrate the possibilities of controlling the magnitude of the magnetoimpedance in a ferromagnet-piezoelectric structure using an electric field. Method. In the measurements, we used a planar heterostructure containing a strip of amorphous ferromagnet Metglas, 25 µm thick and 25 mm long, mechanically connected to a bimorph, 0.5 mm thick and 30 mm long, made of piezoceramic lead zirconate titanate. An alternating current with a frequency of 30 kHz...10 MHz was passed through the strip, the structure was placed in a longitudinal permanent magnetic field of 0...500 Oe, an alternating electric field up to 400 V/cm with a frequency of 60 Hz...50 kHz was applied to the piezobimorph, and the change in the impedance of the strip was recorded. Results. In the absence of electric field, a narrowing of the magnetoimpedance magnetic fields region with a decrease in the current frequency and saturation of the magnetoimpedance in magnetic fields above 334 Oe were observed. The maximum value of the magnetoimpedance reached 18% at a current frequency of 1 MHz. The application of electric field to the piezobimorph led to the appearance of side components in the frequency spectrum of the voltage on the ferromagnetic layer, which indicates the amplitude-phase modulation of the magnetoimpedance. The amplitude modulation coefficient reached a maximum value of 6 · 10−3 for the electric field frequency of 11.2 kHz and decreased monotonically with an increase in the magnetic field. The modulation of the magnetoimpedance occurs due to the converse magnetoelectric effect in the heterostructure, which leads to the modulation of the magnetization of the ferromagnetic layer, and the subsequent change in the relative magnetic permeability and thickness of the skin layer in the ferromagnet. The results obtained can be used to create magnetic fields sensors controlled by an electric field.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76868673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003008
M. Seleznev, Y. Nikulin, Y. Khivintsev, S. Vysotskii, A. Kozhevnikov, V. Sakharov, G. Dudko, Evgenij Pavlov, Y. Filimonov
The purpose of this work is to find out the influence of three-magnon decay processes on the electromotive force (EMF (U)) generated by propagating magnetostatic surface waves (MSSW) with the help of the inverse spin Hall effect in the “yttrium-iron garnet (YIG) – platinum (Pt)” structure. Methods. The experiments were carried out using the delay line structures based on YIG films with the thickness of 8.8 and 14.6 µm, on the surface of which antennas were formed for MSSWs excitation and reception and a Pt film between antennas. Results. It was shown that the three-magnon parametric instability can significantly change the character of EMF dependences on frequency and on power of MSSW that resulted both from the effect of power limitation and from the participation of parametric spin waves (PSW) and secondary spin waves (SSW) in the processes of electron-magnon scattering on the YIG/Pt border. Conclusion. It was demonstrated that the effect of amplification of EMF generation at the frequencies that are close to the long-wavelength border of the MSSW spectrum is related with the PSW and SSW population of the region of anisotropic dipole-exchange spin waves spectrum, which is characterized by the presence of singularities in the magnon density of states (Van Hove singularities).
{"title":"Influence of three-magnon decays on electromotive force generation by magnetostatic surface waves in integral YIG – Pt structures","authors":"M. Seleznev, Y. Nikulin, Y. Khivintsev, S. Vysotskii, A. Kozhevnikov, V. Sakharov, G. Dudko, Evgenij Pavlov, Y. Filimonov","doi":"10.18500/0869-6632-003008","DOIUrl":"https://doi.org/10.18500/0869-6632-003008","url":null,"abstract":"The purpose of this work is to find out the influence of three-magnon decay processes on the electromotive force (EMF (U)) generated by propagating magnetostatic surface waves (MSSW) with the help of the inverse spin Hall effect in the “yttrium-iron garnet (YIG) – platinum (Pt)” structure. Methods. The experiments were carried out using the delay line structures based on YIG films with the thickness of 8.8 and 14.6 µm, on the surface of which antennas were formed for MSSWs excitation and reception and a Pt film between antennas. Results. It was shown that the three-magnon parametric instability can significantly change the character of EMF dependences on frequency and on power of MSSW that resulted both from the effect of power limitation and from the participation of parametric spin waves (PSW) and secondary spin waves (SSW) in the processes of electron-magnon scattering on the YIG/Pt border. Conclusion. It was demonstrated that the effect of amplification of EMF generation at the frequencies that are close to the long-wavelength border of the MSSW spectrum is related with the PSW and SSW population of the region of anisotropic dipole-exchange spin waves spectrum, which is characterized by the presence of singularities in the magnon density of states (Van Hove singularities).","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75016246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003009
V. Poimanov
Purpose of the study is to show that the conditions for the propagation of exchanged spin waves (ESWs) in an asymmetric superlattice with antiferromagnetically ordered cells depend significantly on the chirality of the precession of the ESW magnetization (polarization, “magnon pseudospin”). Method. When constructing the EWS spectra, the Croning– Penny model (transfer-matrix method) and the Landau–Lifshitz equation are used to determine the nature of the waves in the cells. In the case of a uniaxial medium, there is only one type of ESW, therefore, when fields are joined at the boundary, the conservation of chirality is an essential factor due to which the ESW in one cell is always traveling, and in the other — evanescent. Thus, a superlattice for ESW is an effective periodic “potential” in which asymmetry can be realized either by applying an external field, or by a difference in the thickness and/or physical properties of the cell materials. Results. Based on the analysis of the spectrum, maps of the transmission zones for ESW of different chirality were constructed in three representations — “Bloch wave number – frequency”, “frequency – relative cell thickness”, as well as in the plane of cell wave numbers. It is shown that the presence of asymmetry leads to a difference in the width of the transmission zones for waves of different chirality. For a finite structure, the frequency dependences of the transmission and reflection coefficients of the ESW are plotted. An increase in the attenuation of the ESW near the boundaries of the transmission zones was also found. Conclusion. The results of the study can be used in the design of magnon valves and other devices based on ESW, in which their chirality can be controlled.
{"title":"Spectrum of exchange spin waves in a one-dimensional magnonic crystal with antiferromagnetic ordering","authors":"V. Poimanov","doi":"10.18500/0869-6632-003009","DOIUrl":"https://doi.org/10.18500/0869-6632-003009","url":null,"abstract":"Purpose of the study is to show that the conditions for the propagation of exchanged spin waves (ESWs) in an asymmetric superlattice with antiferromagnetically ordered cells depend significantly on the chirality of the precession of the ESW magnetization (polarization, “magnon pseudospin”). Method. When constructing the EWS spectra, the Croning– Penny model (transfer-matrix method) and the Landau–Lifshitz equation are used to determine the nature of the waves in the cells. In the case of a uniaxial medium, there is only one type of ESW, therefore, when fields are joined at the boundary, the conservation of chirality is an essential factor due to which the ESW in one cell is always traveling, and in the other — evanescent. Thus, a superlattice for ESW is an effective periodic “potential” in which asymmetry can be realized either by applying an external field, or by a difference in the thickness and/or physical properties of the cell materials. Results. Based on the analysis of the spectrum, maps of the transmission zones for ESW of different chirality were constructed in three representations — “Bloch wave number – frequency”, “frequency – relative cell thickness”, as well as in the plane of cell wave numbers. It is shown that the presence of asymmetry leads to a difference in the width of the transmission zones for waves of different chirality. For a finite structure, the frequency dependences of the transmission and reflection coefficients of the ESW are plotted. An increase in the attenuation of the ESW near the boundaries of the transmission zones was also found. Conclusion. The results of the study can be used in the design of magnon valves and other devices based on ESW, in which their chirality can be controlled.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72484315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003001
Sergej Grishin
Congratulations to Yuri Pavlovich Sharayevsky on his anniversary.
祝贺尤里·帕夫洛维奇·沙拉耶夫斯基结婚纪念日。
{"title":"On the anniversary of Yuri P. Sharaevsky","authors":"Sergej Grishin","doi":"10.18500/0869-6632-003001","DOIUrl":"https://doi.org/10.18500/0869-6632-003001","url":null,"abstract":"Congratulations to Yuri Pavlovich Sharayevsky on his anniversary.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83603900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003003
M. Morozova, O. Matveev
Purpose of this work is to compile an overview of a new and fruitful scientific direction in magnonics, which grew out of the works of Ph.D., Professor Yuri Pavlovich Sharaevsky, and related to the study of resonant and nonlinear phenomena during the propagation of magnetostatic waves in ferromagnetic films, ferromagnetic films with periodic inhomogeneities (magnonic crystals), coupled (layered and lateral) ferromagnetic structures, as well as ferromagnetic structures with layers of a different physical nature (semiconductor, ferroelectric, piezoelectric, normal metal layers). Methods. Experimental and theoretical methods have been used to study spin-wave excitations in a wide class of structures with ferromagnetic layers. In particular, experimental radiophysical methods of microwave measurements and optical methods of Mandelstam-Brillouin spectroscopy. For the construction of theoretical models, the following methods are used: the method of coupled waves, the method of crosslinking magnetic permeability at the boundaries of layers, the method of transmission matrices, long-wave approximation. Results. The presented results are of general scientific importance for understanding the basic laws of the joint influence of coupling, periodicity and interactions of different physical nature (the influence on the magnetostatic wave of deformation in periodic structures with piezoelectric, electromagnetic wave in structures with ferroelectric, electric current in structures with semiconductor, spin current in structures with normal metal). In applied terms, the identified effects open up wide opportunities for creation of new devices of spin-wave electronics with the possibility of dynamic control of characteristics when changing the electric and magnetic fields, as well as the power of the input signal. Conclusions. The review of the most interesting results obtained by the authors together with Yuri Pavlovich and which are an ideological continuation of the foundations laid by him is given.
{"title":"Resonant and nonlinear phenomena during the propagation of magnetostatic waves in multiferroid, semiconductor and metallized structures based on ferromagnetic films and magnonic crystals","authors":"M. Morozova, O. Matveev","doi":"10.18500/0869-6632-003003","DOIUrl":"https://doi.org/10.18500/0869-6632-003003","url":null,"abstract":"Purpose of this work is to compile an overview of a new and fruitful scientific direction in magnonics, which grew out of the works of Ph.D., Professor Yuri Pavlovich Sharaevsky, and related to the study of resonant and nonlinear phenomena during the propagation of magnetostatic waves in ferromagnetic films, ferromagnetic films with periodic inhomogeneities (magnonic crystals), coupled (layered and lateral) ferromagnetic structures, as well as ferromagnetic structures with layers of a different physical nature (semiconductor, ferroelectric, piezoelectric, normal metal layers). Methods. Experimental and theoretical methods have been used to study spin-wave excitations in a wide class of structures with ferromagnetic layers. In particular, experimental radiophysical methods of microwave measurements and optical methods of Mandelstam-Brillouin spectroscopy. For the construction of theoretical models, the following methods are used: the method of coupled waves, the method of crosslinking magnetic permeability at the boundaries of layers, the method of transmission matrices, long-wave approximation. Results. The presented results are of general scientific importance for understanding the basic laws of the joint influence of coupling, periodicity and interactions of different physical nature (the influence on the magnetostatic wave of deformation in periodic structures with piezoelectric, electromagnetic wave in structures with ferroelectric, electric current in structures with semiconductor, spin current in structures with normal metal). In applied terms, the identified effects open up wide opportunities for creation of new devices of spin-wave electronics with the possibility of dynamic control of characteristics when changing the electric and magnetic fields, as well as the power of the input signal. Conclusions. The review of the most interesting results obtained by the authors together with Yuri Pavlovich and which are an ideological continuation of the foundations laid by him is given.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84317506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003005
V. Tikhonov, V. Gubanov
Purpose of this study is to elucidate the mechanism of transformation of electromagnetic and exchange spin waves (ESW) in a thin transition layer of epitaxial ferrite–dielectric structures, as well as to investigate the possibilities of using short-wave ESW to diagnose magnetic inhomogeneities of epitaxial yttrium-iron garnet (YIG) films. Methods. In this paper, we study the hybridization processes of electromagnetic and exchange spin waves that occur in the transition layer of the YIG film. The features of the dispersion of coupled waves in the vicinity of phase synchronism frequencies under normal and tangential magnetization of the YIG film are investigated. Results. It is shown that within of the thickness transition layer, the dispersion of the excited ESW experiences significant distortions, which manifests itself in frequency shifts of the spin-wave resonance. Based on this, a method for calculating the distribution of spontaneous magnetization over the thickness of the YIG film was proposed, which was used to simulate the processes of excitation of spin-wave resonances. Conclusion. The proposed technique of spin-wave diagnostics of YIG films can be effectively used for non-destructive testing of all types of epitaxial ferrite-dielectric structures, which may be in demand in the field of production and in the field of their practical application.
{"title":"Spin-wave diagnostics of epitaxial ferrite-dielectric structures","authors":"V. Tikhonov, V. Gubanov","doi":"10.18500/0869-6632-003005","DOIUrl":"https://doi.org/10.18500/0869-6632-003005","url":null,"abstract":"Purpose of this study is to elucidate the mechanism of transformation of electromagnetic and exchange spin waves (ESW) in a thin transition layer of epitaxial ferrite–dielectric structures, as well as to investigate the possibilities of using short-wave ESW to diagnose magnetic inhomogeneities of epitaxial yttrium-iron garnet (YIG) films. Methods. In this paper, we study the hybridization processes of electromagnetic and exchange spin waves that occur in the transition layer of the YIG film. The features of the dispersion of coupled waves in the vicinity of phase synchronism frequencies under normal and tangential magnetization of the YIG film are investigated. Results. It is shown that within of the thickness transition layer, the dispersion of the excited ESW experiences significant distortions, which manifests itself in frequency shifts of the spin-wave resonance. Based on this, a method for calculating the distribution of spontaneous magnetization over the thickness of the YIG film was proposed, which was used to simulate the processes of excitation of spin-wave resonances. Conclusion. The proposed technique of spin-wave diagnostics of YIG films can be effectively used for non-destructive testing of all types of epitaxial ferrite-dielectric structures, which may be in demand in the field of production and in the field of their practical application.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82944013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-30DOI: 10.18500/0869-6632-003010
R. Babichev, G. Babicheva
The purpose of this work is the study of design of new short-circuited coaxial transducer with thin linear jumper, that circuites on both sides of the grounded coaxial cylinder, located above the rectangular iron-yttrium garnet (YIG) film, in homogeneous constant magnetic field with rectangular film along its length or width. The thin linear jumper is directed parallel to the width of the YIG film. Methods. In the CST Microwave Studio environment, an electrodynamic analysis of the model was carried out using the finite element method. To study the efficiency of modes excitation in a ferrite film at different distances between the coaxial transducer and the surface of the YIG film, the frequency dependencies of the inverse losses S11 of the model were calculated. Results. 1. The identification of modes in a homogeneous static magnetic field H, directed parallel to the plane of a rectangular YIG film along its width (y-axis) was carried out. 2. The identification of modes in a homogeneous static magnetic field H directed parallel to the plane of the rectangular YIG film along its length (z-axis) was carried out. 3. A comparison of modes spectra was made at H, directed parallel to the plane of the YIG film along its width (y axis) and length (z axis). Conclusion. In this paper short-circuited transducer with a thin linear jumper, circuited on both sides of the grounded coaxial cylinder, is investigated. By the electrodynamic method distributions of high-frequency magnetic field of the excited magnetostatic modes were calculated and their identification was carried out for two directions of homogeneous static magnetic field: along width and along length of rectangular YIG film. The dependence of number of excited modes on the distance between a short-circuited transducer and rectangular YIG was also studied. A comparison of modes spectra is carried out at H, directed parallel to the plane of the YIG film along its width and length. With this rotation of H vector, the band of effectively excitable modes shifts from 4.6...4.9 GHz to 4.5...4.75 GHz. However, the excitation of these modes in the case of the vector H, directed along the width of YIG film (z-axis), is much more effective in the band 4.65...4.9 GHz than in the case when this vector is directed along the length of YIG film (z-axis). At the same time, excitation of these modes in the case of the vector H, directed along the length of YIG film (z axis) is much more effective in the band 4.4...4.6 GHz.
{"title":"Excitation by shot circuited coaxial transducer of magnetostatic modes in rectangular yttrium iron garnet film","authors":"R. Babichev, G. Babicheva","doi":"10.18500/0869-6632-003010","DOIUrl":"https://doi.org/10.18500/0869-6632-003010","url":null,"abstract":"The purpose of this work is the study of design of new short-circuited coaxial transducer with thin linear jumper, that circuites on both sides of the grounded coaxial cylinder, located above the rectangular iron-yttrium garnet (YIG) film, in homogeneous constant magnetic field with rectangular film along its length or width. The thin linear jumper is directed parallel to the width of the YIG film. Methods. In the CST Microwave Studio environment, an electrodynamic analysis of the model was carried out using the finite element method. To study the efficiency of modes excitation in a ferrite film at different distances between the coaxial transducer and the surface of the YIG film, the frequency dependencies of the inverse losses S11 of the model were calculated. Results. 1. The identification of modes in a homogeneous static magnetic field H, directed parallel to the plane of a rectangular YIG film along its width (y-axis) was carried out. 2. The identification of modes in a homogeneous static magnetic field H directed parallel to the plane of the rectangular YIG film along its length (z-axis) was carried out. 3. A comparison of modes spectra was made at H, directed parallel to the plane of the YIG film along its width (y axis) and length (z axis). Conclusion. In this paper short-circuited transducer with a thin linear jumper, circuited on both sides of the grounded coaxial cylinder, is investigated. By the electrodynamic method distributions of high-frequency magnetic field of the excited magnetostatic modes were calculated and their identification was carried out for two directions of homogeneous static magnetic field: along width and along length of rectangular YIG film. The dependence of number of excited modes on the distance between a short-circuited transducer and rectangular YIG was also studied. A comparison of modes spectra is carried out at H, directed parallel to the plane of the YIG film along its width and length. With this rotation of H vector, the band of effectively excitable modes shifts from 4.6...4.9 GHz to 4.5...4.75 GHz. However, the excitation of these modes in the case of the vector H, directed along the width of YIG film (z-axis), is much more effective in the band 4.65...4.9 GHz than in the case when this vector is directed along the length of YIG film (z-axis). At the same time, excitation of these modes in the case of the vector H, directed along the length of YIG film (z axis) is much more effective in the band 4.4...4.6 GHz.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80226514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-01DOI: 10.18500/0869-6632-2022-30-4-436-455
A. Perevaryukha
Purpose is to develop a mathematical model for the analysis of a variant in the development of a population process with a non-trivially regulated confrontation between an invading species and a biotic environment. Relevance. The situation we are studying arises in invasive processes, but is a previously unexplored special variant of their development. The task of modeling is to describe the transition to a deep ν-shaped crisis after intensive growth. The model is based on examples of the adaptive dynamics of a bacterial colony and the suppression of mollusk populations, carriers of dangerous parasitic diseases, after targeted anti-epidemic introduction of their antagonists. Methods. In our work equations with a retarded argument in the range of parameter values that have a biological interpretation were studied. The model uses a logarithmic form of species regulation, taking into account the theoretically permissible capacity of the medium. In the equation we included the function of external influence with flexible threshold regulation relative to the current and previous population size. Results. It is shown that the proposed form of impact regulation leads to the formation of a stable adapted population after the crisis, which does not have a destructive impact on the habitat. With an increase in the reproductive potential of an invasive species, a deep crisis becomes critically dangerous. The form of the crisis passage depends on the reproductive potential, on the size of the initial group of individuals, and also on the time of activation of the adaptive counteraction from the environment. It is established that at a sufficient level of resistance, a non destructive equilibrium is established. Conclusion. The actual scenario of sudden depression of an actively spreading population with a large reproductive 𝑟-parameter, which is caused by the delayed activity of its natural antagonists, has been studied. The threshold form of biotic regulation is characteristic of insects, the abundance of which is regulated by competing species of parasitic hymenoptera. The variant of rapid phase change considered by us in the model is relevant as a description of one of the forms of developing the body’s immune response to the development of an acute infection with a significant delay. If the immune response is prematurely inhibited by the body itself, then the chronic focus of the disease persists. Examples of the dynamics of two real biological processes in experiments with biological suppression methods are given, which correspond to the invasion scenario obtained in the new model.
{"title":"Modeling of adaptive counteraction of the induced biotic environment during the invasive process","authors":"A. Perevaryukha","doi":"10.18500/0869-6632-2022-30-4-436-455","DOIUrl":"https://doi.org/10.18500/0869-6632-2022-30-4-436-455","url":null,"abstract":"Purpose is to develop a mathematical model for the analysis of a variant in the development of a population process with a non-trivially regulated confrontation between an invading species and a biotic environment. Relevance. The situation we are studying arises in invasive processes, but is a previously unexplored special variant of their development. The task of modeling is to describe the transition to a deep ν-shaped crisis after intensive growth. The model is based on examples of the adaptive dynamics of a bacterial colony and the suppression of mollusk populations, carriers of dangerous parasitic diseases, after targeted anti-epidemic introduction of their antagonists. Methods. In our work equations with a retarded argument in the range of parameter values that have a biological interpretation were studied. The model uses a logarithmic form of species regulation, taking into account the theoretically permissible capacity of the medium. In the equation we included the function of external influence with flexible threshold regulation relative to the current and previous population size. Results. It is shown that the proposed form of impact regulation leads to the formation of a stable adapted population after the crisis, which does not have a destructive impact on the habitat. With an increase in the reproductive potential of an invasive species, a deep crisis becomes critically dangerous. The form of the crisis passage depends on the reproductive potential, on the size of the initial group of individuals, and also on the time of activation of the adaptive counteraction from the environment. It is established that at a sufficient level of resistance, a non destructive equilibrium is established. Conclusion. The actual scenario of sudden depression of an actively spreading population with a large reproductive 𝑟-parameter, which is caused by the delayed activity of its natural antagonists, has been studied. The threshold form of biotic regulation is characteristic of insects, the abundance of which is regulated by competing species of parasitic hymenoptera. The variant of rapid phase change considered by us in the model is relevant as a description of one of the forms of developing the body’s immune response to the development of an acute infection with a significant delay. If the immune response is prematurely inhibited by the body itself, then the chronic focus of the disease persists. Examples of the dynamics of two real biological processes in experiments with biological suppression methods are given, which correspond to the invasion scenario obtained in the new model.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78765890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-01DOI: 10.18500/0869-6632-2022-30-4-495-512
E. Navrotskaya, D. Kulminskiy, V. Ponomarenko, Mihail Prokhorov
Aim of the study is to develop a method for estimating the parameters of an external periodic impulse action using a spiking network of neuronlike oscillators. Methods. The spiking activity of a network consisting of coupled nonidentical neuronlike FitzHugh–Nagumo oscillators was studied, depending on the parameters of the periodic impulse action. To estimate the amplitude of the external impulse signal, we detuned the FitzHugh–Nagumo oscillators, which were in a stable state of equilibrium in the absence of an external action, by the threshold parameter responsible for the excitation of the oscillator. To estimate the frequency of excitatory pulses, we detuned the FitzHugh–Nagumo oscillators by the parameter characterizing the ratio of time scales, the value of which determines the natural frequency of oscillators. We also changed the duration of external pulses. Results. It is shown that the number of spikes generated by a network of nonidentical FitzHugh–Nagumo oscillators has a monotonic dependence on the amplitude of the external pulse signal and a nonmonotonic dependence on the frequency of the pulse signal. The number of spikes generated by the network remains constant over a wide range of external pulse durations. A method for estimating the amplitude and frequency of impulse action is proposed. The method efficiency is demonstrated in numerical simulations and in a radio physical experiment. Conclusion. The proposed method allows one to estimate the amplitude of an external pulse signal, knowing its frequency, and estimate the frequency of this signal, knowing its amplitude. The method can be used in robotics when solving the problems of information processing related to the motion control of mobile robots.
{"title":"Estimation of impulse action parameters using a network of neuronlike oscillators","authors":"E. Navrotskaya, D. Kulminskiy, V. Ponomarenko, Mihail Prokhorov","doi":"10.18500/0869-6632-2022-30-4-495-512","DOIUrl":"https://doi.org/10.18500/0869-6632-2022-30-4-495-512","url":null,"abstract":"Aim of the study is to develop a method for estimating the parameters of an external periodic impulse action using a spiking network of neuronlike oscillators. Methods. The spiking activity of a network consisting of coupled nonidentical neuronlike FitzHugh–Nagumo oscillators was studied, depending on the parameters of the periodic impulse action. To estimate the amplitude of the external impulse signal, we detuned the FitzHugh–Nagumo oscillators, which were in a stable state of equilibrium in the absence of an external action, by the threshold parameter responsible for the excitation of the oscillator. To estimate the frequency of excitatory pulses, we detuned the FitzHugh–Nagumo oscillators by the parameter characterizing the ratio of time scales, the value of which determines the natural frequency of oscillators. We also changed the duration of external pulses. Results. It is shown that the number of spikes generated by a network of nonidentical FitzHugh–Nagumo oscillators has a monotonic dependence on the amplitude of the external pulse signal and a nonmonotonic dependence on the frequency of the pulse signal. The number of spikes generated by the network remains constant over a wide range of external pulse durations. A method for estimating the amplitude and frequency of impulse action is proposed. The method efficiency is demonstrated in numerical simulations and in a radio physical experiment. Conclusion. The proposed method allows one to estimate the amplitude of an external pulse signal, knowing its frequency, and estimate the frequency of this signal, knowing its amplitude. The method can be used in robotics when solving the problems of information processing related to the motion control of mobile robots.","PeriodicalId":41611,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedeniy-Prikladnaya Nelineynaya Dinamika","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80344669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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