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Waveguide-dielectric Resonance in Systems with Nanometer Metal Layer on Dielectric Substrate

Authors: Usanov D. A., Skripal A. V., Ponomarev D. V., Latysheva E. V., Feklistov V. B.

High sensitivity of an electromagnetic wave transmission spectra to change the thickness of the nanometer metal layers on dielectric plates in the case of the waveguide-dielectric resonance emergence due to the waveguide cross section is partially filled across the width and asymmetrically occupied relative to its middle by the investigated structure has been established.

From Anosov’s Dynamics on a Surface of Negative Curvature to Electronic Generator of Robust Chaos

Authors: Kuznetsov S. P.

Background and Objectives: Systems with hyperbolic chaos should be of preferable interest due to structural stability (roughness) that implies insensitivity to variation of parameters, manufacturing imperfections, interferences, etc. However, until recently, exclusively formal mathematical examples of this kind of dynamical behavior were known.

Poincare Recurrences and Afraimovich–Pesin Dimension in a Nonautonomous Conservative Oscillator

Authors: Galaktionova T. I., Semenova N. I., Anishchenko V. S.

Background and Objectives: One of the fundamental features of the temporal dynamics is Poincare recurrence. It have been shown that statistics of return time in global approach depends on topological entropy h. The case of h > 0 (set with mixing) has been already studied theoretically. The theoretical conclusions have been confirmed by numerical simulation. The case of the sets without mixing (h = 0) has been studied theoretically, but recent numerical results shows some special aspects which are absent in theory.

Two Approaches to the Solution of the Scalar Problem of Diffraction on the Plane Two-periodic Lattice From Bodies of Revolution Located in the Liquid Layer

Authors: Manenkov S. А.

Background, Objectives and Methods: The problem of diffraction of acoustic waves on the lattices located in the layered media is of great scientific interest in hydroacoustics. There are many methods of the solution of this diffraction problem, such as the method of the surface integral equations, finite element method, boundary element method, etc. One of universal method of solution of diffraction problems is the modified method of discrete sources (MMDS).

Method for Information Transmission Using a Predictive Model in Coupled Time-delay Systems

Authors: Prohorov M. D., Ponomarenko V. I., Chub R. О.

Background and Objectives: The object of our study is a system for secure information transmission based on time-delay generators. The choice of the model is justified by the fact that time-delay systems can be easily realized in experiment and they can exhibit chaotic behavior with a large number of positive Lyapunov exponents (hyperchaos). A transmitter uses the modulation of the delay time of a chaotic generator by a binary information signal.

Calculation of Focusing Spin Wave Transducers Using the Method of Micromagnetic Simulation

Authors: Dudko G. М., Kozhevnikov А. V., Saharov V. К., Stalmahov А. V., Filimonov Y. А., Khivintsev Y. V.

Background and Objectives: Researches in the field of electronic circuit development for microwave informational systems based on magnetization oscillations and waves have been performing since the 1960s of the last century. The surge of interest in spin waves (SW) during the last decade is caused by the perspective to use SW as information carriers on the sub-micromagnetic and nanometer scale that leads to the fabrication of devices on magnonic principles and a significant miniaturization of spin-wave devices.

Synchronization of Chimera States in Ensembles of Nonlocally Coupled Cubic Maps

Authors: Anishchenko V. S., Kholuianova I. А., Bogomolov S. А.

Background and Objectives: Effects of mutual and external synchronization of chimera states are studied in two coupled ensembles of discrete maps. Each of the ensembles is a onedimensional ring of nonlocally coupled cubic maps in the chaotic oscillation mode. In order to create differences in the dynamics of the ensembles when there is no coupling between them, a mismatch is introduced in the parameters of the individual oscillators of the first and second rings. Effects of external and mutual synchronization of chimera states are explored in detail.

Lorenz Attractor in a System with Delay: an Example of Pseudogyperbolic Chaos

Authors: Kuznetsov S. P., Kuptsov P. V.

Background and Objectives: The work contributes to a research direction aimed at search for and construction of physically realizable systems, which could fill the mathematical theory of pseudo-hyperbolic dynamics with physical content. Chaotic attractors belonging to this class generate genuine chaos that does not degrade under small variations of parameters and functions in dynamical equations.

Numerical Simulation of a Looped Tube 4-Stage Traveling-Wave Thermoacoustic Engine

Authors: Gorshkov I. B., Petrov V. V.

Background and Objectives: The technology of thermoacoustic energy conversion is one of the most promising technologies for converting thermal energy into electrical one. A brief review of the achievements in development of the multi-stage traveling-wave engines was made. The numerical simulation of a 4-stage engine with a load was done. The aim of research was to determine the engine parameters, required to achieve the maximum of efficiency of the system and the acoustic power on the load.

Complex Dynamics and Chaos in the Rabinovich – Fabrikant Model

Authors: Kuznetsov A. P., Kuznetsov S. P., Turukina L. V.

Background and Objectives: In the work we consider a finitedimensional three-mode model of the nonlinear parabolic equation. It was proposed in 1979 by M. I. Rabinovich and A. L. Fabrikant. It describes the stochasticity arising from the modulation instability in a non-equilibrium dissipative medium with a spectrally narrow amplification increment. The Rabinovich – Fabrikant system presents some extremely rich dynamics die to the third-order nonlinearities presented in the equations. The considered system is universal.

On the Theory of Synchronization of a Two-Mode Electron Maser with a Hard Excitation

Authors: Adilova A. B., Preobrazhenskaya N. V., Ryskin N. M.

Background and Objectives: Medium-power (10–100 W) THz continuous-wave electron cyclotron masers (gyrotrons) are of great interest for many applications, such as spectroscopy with dynamic nuclear polarization, plasma diagnostics, non-destructive testing, remote detection of radioactive materials, biomedical applications, etc. For these applications, a high frequency stability is required, with the possibility of frequency tuning within 1–2 GHz.

Linear Model of Surface Terahertz Plasmons Amplification in Two Parallel Graphene Sheets

Authors: Morozov M. Y., Moiseenko I. M., Popov V. V.

Amplification of terahertz plasmons in a pair of parallel active graphene monolayers is studied theoretically. It is shown that the antisymmetric mode increment of plasmons in the two parallel graphene monolayers may be several times greater than that in a single graphene layer due to deceleration of the antisymmetric plasmon mode as compared to the plasmon mode in a single graphene monolayer.

Spatiotemporal Structures in an Ensemble of Nonlocally Coupled Nekorkin Maps

Authors: Bogomolov S. А., Rybalova E. V., Strelkova G. I., Anishchenko V. S.

Background and Objectives: Studying chimera states is a subject of special attention among specialists in nonlinear dynamics, and the issue on the mechanisms for implementing chimeras is today one of the topic directions. In the paper we consider the mechanism for realizing a chimera state regime which is based on the so-called “solitary states” (SSC) and is actively discussed by experts. The problem is solved by analyzing the dynamics of a one-dimensional ring of nonlocally coupled discrete-time systems.

Negative Dispersion, Refraction and Backward Polaritons: Impedance Approach

Authors: Davidovich M. V.

Background and Objectives: The dispersion equations of surface plasmon-polaritons are derived for the general case of layered dissipative structures. The waves are classified as gliding with energy flow into structure from vacuum and leakage ones. The dispersion equations and conditions for the existence of slow and fast gliding and leaky waves, as well as forward and backward waves are considered.

Simulation of a Sub-THz Traveling Wave Tube with Multiple Sheet Electron Beam

Authors: Ploskikh A. E., Ryskin N. M.

Background and Objectives: Many applications, such as highdata-rate wireless communications, spectroscopy, high-resolution radar, biomedical imaging, security, etc. require compact highpower sources of sub-THz radiation. Traveling wave tube (TWT) amplifiers are the most promising candidates for such sources combining 10–100 W power and wide b andwidth. Here we present the results of design and simulation of a 0.2 THz TWT with a grating slow-wave structure (SWS) and electron-optical system (EOS) with three elliptic-sha ped beams.

Spiral Wave Patterns in Two-Layer 2D Lattices of Nonlocally Coupled Discrete Oscillators. Synchronization of Spiral Wave Chimeras

Authors: Bukh A. V., Strelkova G. I., Anishchenko V. S.

The paper describes the spatio-temporal dynamics of a lattice that is given by a 2D N × N network of nonlocally coupled Nekorkin maps which model neuronal activity. The network behavior is studied for periodic and no-flux boundary conditions. It is shown that for certain values of the coupling parameters, rotating spiral waves and spiral wave chimeras can be observed in the considered lattice. We analyze and compare statistical and dynamical characteristics of the local oscillators from coherence and incoherence clusters of a spiral wave chimera.

The Method of Visualization of Spatially Inhomogeneous Acousic Fields from Micro-Objects on the Basis of Acousto-Optic Interaction in the System with Double Fourier Transform

Authors: Nikishin E. L., Pavlova M. V., Suchilin A. V.

Background and Objectives: The method of acousto-optic visualization based on a double Fourier transform is presented. In a hybrid acousto-optic processor, the double Fourier transform is realized in the process of converting an acoustic signal from an object by an acoustic lens formed by the conjugate spherical surfaces of two crystals, and the subsequent processing of light diffracted in a photoelastic medium by an optical collecting lens.

Chimera Structures in Ensembles of Nonlocally Coupled Sprott Maps

Authors: Puzanov A. M., Anishchenko V. S., Strelkova G. I.

Background and Objectives: Recently, special attention in nonlinear dynamics and related research fields was targeted to the study of chimera states in networks of coupled oscillators. Chimeras were revealed in ensembles of nonlocally coupled identical systems which are described by both discrete- and continuous-time chaotic systems. In the paper we study numerically the dynamics of ring networks of nonlocally coupled chaotic discrete maps in order to find chimera states of different types, namely, phase and amplitude chimeras.

Control of Collective Dynamics in a Network of Bistable Time-Delay Systems Coupled via the Mean Field

Authors: Ponomarenko V. I., Kulminskiy D. D., Borovkova E. I., Prohorov M. D.

Background and Objectives: The object of our study is a network of identical bistable time-delayed feedback systems coupled via the mean field and driven by an external harmonic signal. The mean field that provides the global coupling of time-delay systems has its own delay time, which allows one to take into account the final speed of signal propagation and processing in the medium through which the oscillators are connected.