Here we study the spin -wave propagation in a system of Mach-Zehnder interferometers (MZI) based on ferrimagnetic yttrium -iron garnet (YIG) thin film. The angular momentum transfer during the excitation of a surface magnetostatic spin wave and the coupling of the spin -waves inside the adjacent arms of MZIs is studied using the micromagnetic modeling method. The local variation of the YIG magnetization inside the arms of MZI manifests itself both in the phase shift of the propagating spin -wave signal and coupling efficiency in the region where the adjacent arms of MZI are placed in the close proximity to each other. The switching/demultiplexing performance which is reflected in the spatial frequency selection of the spin -wave signal upon dynamical local change of the magnetization in each of four arms of the interferometers is demonstrated. The proposed MZI demonstrates the basis for the realization of the set of logical operations and could serve the facility of add and drop frequencies (channels) to and from a magnonic data bus in frequency division multiplexed magnonic networks. The use of laterally coupled interferometers opens new possibilities for the formation of the logical magnon devices tuned by the local variation of magnetization which could be realized with the locally focused laser heating.

Using numerical and experimental methods, the mechanism of control of the transmission of a spin-wave signal in a three-dimensional magnon splitter, formed by an orthogonal junction of magnetic strips of yttrium iron garnet, has been investigated. It is shown that by variation the size of the air gap between the spin-waveguide sections, it is possible to control the selection of the signal propagating in the output sections of the structure. From an applied point of view, the results obtained can be used to create an interconnection element in multilevel magnon information processing devices for the formation of multilayer magnon network topologies and miniaturization of computing devices based on the principles of magnonics. Key words: spin waves, magnonics, three-dimensional interconnections, micromagnetic modeling. Keywords: spin waves, magnonic, micromagnetic simulations, three-dimensional structure.

Purpose. Investigation of spin-wave signal passage in a system of magnetic microwaves separated from each other by a one-dimensional array of holes. Using numerical and experimental methods to show controlled spatial-frequency selection of the signal in linear and nonlinear modes of operation. Methods. Micromagnetic modeling of the spatial intensity distributions of spin waves. Obtaining S-parameters of spin waves propagating in a tangentially magnetized structure using a vector circuit analyzer. Results. The spatially selective properties of the structure in linear and nonlinear modes are demonstrated using micromagnetic modeling. A mechanism for controlling the frequency range of the Bragg zone is revealed using a vector analyzer. Conclusion. The proposed structure can be used as a functional element in planar topologies of magnon networks and parallel signal processing devices based on them.

Here we present the nonreciprocal propagation of caustic beams and channeling of the backward volume spin wave in an yttrium-iron-garnet structure with the longitudinal symmetry axis and broken translational symmetry. The experimental method of Brillouin spectroscopy and the numerical micromagnetic methods are used to study the mechanisms of control of the nonreciprocal spin-wave signal propagation in a Tshaped junction with a partially metallized surface. It is shown that the partial metallization of the surface together with the reversal of the magnetic field direction can serve as a way to control the propagation of spin-wave beams. The formation of the spin-wave channel between the metal stripe and the edge of the magnetic film is observed experimentally and demonstrated by numerical solution of the Landau-LifshitzGilbert equation and Maxwell's equations. The proposed theoretical analysis explains the experimental results and provides useful technical information for the fabrication of reconfigurable magnonic devices, which utilize the spin-wave beam formation in the region of the junction of the magnonic waveguides with different widths. The proposed structure can be used as a functional element of signal branching and/or power division in magnonic networks and signal-processing devices based on them.

Here we present the results of the study of the joint manifestation of the effects of anisotropic spin waves (SW) propagation in a system of laterally and vertically coupled ferrimagnetic microwaveguides when both the magnetization angle and air gap between waveguide are changed. The micromagnetic modeling method based on the numerical solution of the Landau–Lifshitz–Hilbert equation was used to provide the possibility of controlling the direction of SW propagation in a system of laterally and vertically coupled iron-yttrium garnet (YIG) microwaveguides by changing the magnetization angle and direction of the equilibrium of magnetization direction. The spatial distributions of the dynamic magnetization out-of-plane component of the SW excited in two microwaveguides located on the same substrate obtained in micromagnetic simulations indicate a change in the nature of the SW power localization in the output sections of the microwaveguides. The variation of the magnetization angle of the array leads to the variation of the transverse width of the spin-wave beam and localization of the amplitude maximum in each of the microwaveguides within the array. The joint manifestation of dipole coupling effects in each separately taken layer of the structure realizes the regime of non-diffraction propagation of the spin-wave beam.

We investigated a spin-wave propagation in a magnon-crystal structure formed from two lateral microwaveguides separated by a one-dimensional antidot array. The mechanisms of control of the backpropagating regime of the surface spin waves both with geometry tuning and with power level variation in the case of in-plane magnetization are investigated by the method of micro-magnetic modeling and the experimental method of Brillouin light scattering spectroscopy. It was shown that for the case of spin-waves propagation through the isolated channels the shape anisotropy in the coupling region can be tuned effectively by a variation of the distance between the channels. The regime of nonlinear switching of the signal and backward propagation was observed in microwave and Brillouin spectroscopy measurements. The proposed effect of the signal separation manifests itself in the spatially and frequency-selective regimes of spin-wave propagation. Proposed spin-wave coupler opens an alternative way for the design of the functional interconnections of spin-wave based units in the planar magnonic networks.

In this work, we demonstrate the numerical and experimental research of the spin-wave transport in a structure composed of a gallium arsenide (GaAs) stripe lattice interfaced to an yttrium iron garnet layer. We show that this structure can be considered as an array of an infinite number of laterally coupled ferrite-semiconductor waveguides. We show that the surface wave properties for colinear propagation along the semiconductor stripes are similar to the waves in magnetic films with partial metallization. In addition, the properties of these surface waves depend on the electron concentration of the GaAs and thus may be tuned. With regard to the wave propagation at a certain angle to the GaAs stripe lattice, the Bragg resonance forms and the corresponding band gap depend on the angle between the wave to the stripes and on the GaAs electron density. The Brillouin light scattering technique was used to experimentally observe the spin-wave beam transformation, and microwave measurements support the numerical data and reveal the mechanism of the dip formation and widening of the frequency range in the spin-wave transmission. The proposed structure could be used as a reconfigurable metasurface and magnonic beam separation unit.

Here we propose the different simple building block of the three-dimensional (3D) magnonic network in the form of the joined orthogonal sections of magnonic waveguides. It was shown, that the proposed 3D structures allows the transmission of spin-wave signals in the regime of surface magnetostatic wave propagation without the significant losses due to the junction region. Micromagnetic simulation was used to reveal the mechanism of spin-wave propagation across 3D junction. An electrodynamic problem is considered by the finite element method and the dispersion characteristics of spin waves (SW) are constructed with a change in the geometric parameters of the meander. The nature of the change in the frequency ranges of the Bragg band gaps depending on the meander profile has been studied in detail. It was demonstrated that spin-wave waveguiding 3D structure with broken translational symmetry exploiting the vertical spin-wave transport provides the transmission of the information signal in three-dimensional configuration of magnonic networks.

The dynamics of spin waves during their multimode propagation in a magnonic crystal, which is an irregular narrow ferrite waveguide with periodic boundary modulation, has been studied by the method of Mandelstam--Brillouin spectroscopy. The transformation of the mode composition of spin waves propagating in an irregular ferrite waveguide is shown. The space-time dynamics of spin waves and the characteristics of the band gaps of a magnonic crystal are experimentally studied, and the possibility of controlling the frequency-selective properties of such a structure is shown. By excitation of a superposition of even or odd width modes of the ferrite microstructure, it becomes possible to control the position of the band gaps of a magnonic crystal. The results of the experiment agree with the results of micromagnetic modeling of the propagation and transformation of the spectrum of spin waves propagating in a ferromagnetic periodic structure. Keywords: spin waves, magnonics, magnonic crystal, micromagnetic modeling.

The dynamics of spin waves during their multimode propagation in a magnonic crystal, which is an irregular narrow ferrite waveguide with periodic boundary modulation, has been studied by the method of Mandelstam-Brillouin spectroscopy. The transformation of the mode composition of spin waves propagating in an irregular ferrite waveguide is shown. The space-time dynamics of spin waves and the characteristics of the band gaps of a magnonic crystal are experimentally studied, and the possibility of controlling the frequency-selective properties of such a structure is shown. By excitation of a superposition of even or odd width modes of the ferrite microstructure, it becomes possible to control the position of the band gaps of a magnonic crystal. The results of the experiment agree with the results of micromagnetic modeling of the propagation and transformation of the spectrum of spin waves propagating in a ferromagnetic periodic structure.

In this article, we experimentally demonstrate the propagation of magnetostatic surface spin wave (MSSW) in the orthogonally joined yttrium iron garnet stripes in the form of T-shaped connection. By the means of microwave spectroscopy technique, we show how the transmission is affected by the distance between orthogonal yttrium iron garnet stripes. Micromagnetic modeling demonstrates the presence of nonreciprocal propagation of spin waves (SWs) between all three ports of the T-junction. A mechanism for controlling the spatial-frequency selection of a propagating signal by variation of the air gap in the area of connected orthogonal sections is shown. The proposed structure can act as a magnonic splitter for 3-D topology of multilevel magnonic networks (MNs). The transition to a multilayer topology of MNs opens the possibility of increase of the packing density of computational units based on the principles of magnonics.

Spin-wave transport across multidimensional networks of magnonic waveguides represents a cru-cial and necessary aspect of prospective densely packed three-dimensional spin-wave architectures. Here, we report the results of investigations of spin-wave propagation through magnonic waveguides extending along and bending across two and three dimensions. We consider three designs of in-plane two-dimensional bends, namely with right-angled, diagonal, and curved geometries. Our numerical and experimental results show that such bends facilitate the conversion of spin-wave types, with the out-put modal number depending on the spin-wave frequency. At the same time, variation of the width of lateral magnonic bends enables the spin-wave wavelength to be modified. When propagating across three-dimensional waveguide bends in the form of out-of-plane junctions, the spin-wave wavelength can similarly be tuned by adjusting the stripe's thickness. Our results show that magnonic waveguides can serve not only as passive conduits but also as active elements in modifying the properties of the transmitted spin wave in three-dimensional magnonic networks.

The purpose of research is to study of characteristics of the Fano resonance in a coupled system of nonlinear microwave-guides and resonators depending on geometric parameters of the systems, magnitude of the coupling between them, and the intensity of spin waves. Methods. Linear and nonlinear spin-wave excitations in lateral systems of irregular microwave-guides and resonators based on films of yttrium iron garnet are considered. Using micromagnetic simulation of spin-wave excitations and numerical integration of the coupled wave equation system, the transfer characteristics of the "microwave-guide - resonator" system and the Fano resonance parameters are calculated taking into account the cubic nonlinearity of magnetic media. Results. Based on the numerical integration of the system of equations of coupled waves that take into account the cubic nonlinearity of the magnetic media, theoretical studies have been carried out of the dependences of the transfer and phase characteristics of the "microwave-guide - resonator" system on the intensity of surface spin waves. Features of the demonstration of constructive and destructive interference of spin waves at Fano resonance are studied. Dependences of characteristics of the parameters of the Fano nonlinear resonance (asymmetry coefficient, resonance frequency shifts) on the intensity of spin-wave excitations are established. Conclusion. Results can be used to create spin-wave demultiplexers, power dividers and microwave couplers based on the lateral system of magnetic waveguides as a threshold element for neuromorphic networks, etc.

In this work, the propagation of spin waves in translational symmetry broken irregular magnonic waveguide is investigated. The mechanism of the transfer of the magnetic moment and the conversion of spin waves from backward volume to surface waves is revealed. Mechanisms for controlling spin-wave transport by changing the direction of an external magnetic field are investigated by the method of micromagnetic modeling. The results of studies of structures with broken translational symmetry open up new possibilities for the formation of multilayer magnonic networks of various topologies and miniaturization of computing devices based on the principles of magnonics.

Using numerical and experimental methods, the mechanism of control of the transmission of a spin-wave signal in a three-dimensional magnon splitter, formed by an orthogonal junction of magnetic strips of yttrium iron garnet, has been investigated. It is shown that by variation the size of the air gap between the spin-waveguide sections, it is possible to control the selection of the signal propagating in the output sections of the structure. From an applied point of view, the results obtained can be used to create an interconnection element in multilevel magnon information processing devices for the formation of multilayer magnon network topologies and miniaturization of computing devices based on the principles of magnonics. Key words: spin waves, magnonics, three-dimensional interconnections, micromagnetic modeling.

Spin-wave transport in a lateral system of microwaveguides coupled to each other through a magnonic crystal structure with a one-dimensional array of holes has been analyzed. Mechanisms of controlling a spin-wave signal at the tangential magnetization of the structure have been studied by the micromagnetic simulation and Brillouin spectroscopy. It has been shown that the anisotropy of the shape in region of coupling of spin waves propagating through isolated channels can be effectively changed under the variation of the magnetization angle of the structure, which allows controlling spatial and frequency selective regimes of spin-wave transport. The proposed structure can be used as a functional element of interconnections in planar topologies of magnonic networks and devices for parallel processing of a signal based on them.

We have studied the properties of spin-wave excitations in a structure that is a junction of two regular magnon waveguides. The proposed structure enables the transmission of spin-wave signals in an irregular structure in the propagation mode of a surface magnetostatic wave. Using the method of micromagnetic simulation, the characteristics of the wave process have been calculated when changing the structure parameters, magnitude and direction of a magnetization field. It is shown that a system with translational symmetry violation can be used to transmit a signal in three-dimensional configurations of magnon networks.

AbstractWe have studied the properties of spin-wave excitations in a structure that is a junction of two regular magnon waveguides. The proposed structure enables the transmission of spin-wave signals in an irregular structure in the propagation mode of a surface magnetostatic wave. Using the method of micromagnetic simulation, the characteristics of the wave process have been calculated when changing the structure parameters, magnitude and direction of a magnetization field. It is shown that a system with translational symmetry violation can be used to transmit a signal in three-dimensional configurations of magnon networks.