Papers by Andrei I . Maimistov
Zhurnal Eksperimentalnoi i Teoreticheskoi Fiziki, Mar 1, 1988
The formation of a solitary wave whose parameters are independent of the initial amplified pulse ... more The formation of a solitary wave whose parameters are independent of the initial amplified pulse and dependent only on the gain medium parameters (the gain itself and the gain saturation constant) is observed in a nonlinear gain dispersive medium via numerical experiments. The numerical experiments are carried out for initial pulses with regular amplitude and phase modulation and for stochastic
Journal of Physics: Conference Series, 2016
We consider the coupled forward and backward waves propagating in two dimensional array of wavegu... more We consider the coupled forward and backward waves propagating in two dimensional array of waveguide, which are featured by a positive and negative refraction indexes. The existence of the flat band under certain conditions is demonstrated.
Quantum Electronics, 2015
We consider a nonlinear coupler formed by two tunnelcoupled waveguides, one waveguide being made ... more We consider a nonlinear coupler formed by two tunnelcoupled waveguides, one waveguide being made of a conventional dielectric and the other-of a negative-index material. The possibility of the formation of solitary waves from continuous radiation having a constant intensity is shown provided that the radiation is coupled into the input of a negative-index coupler channel (on the back side of the waveguide system). With increasing intensity of the input light, the speed and amplitude of the generated solitary waves increase and the period of their formation is reduced.
Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 1999
ABSTRACT
Contemporary Optoelectronics, Sep 12, 2015
We consider the coupled electromagnetic waves propagating in a nonlinear coupler and in nonlinear... more We consider the coupled electromagnetic waves propagating in a nonlinear coupler and in nonlinear waveguide array, which consists of alternating waveguides of positive and negative refraction indexes. The forward wave and backward wave interaction is realized in these devices. Gap solitons in a nonlinear oppositely directional coupler with one channel or both channels fabricated from nonlinear medium having negative refraction index are discussed. Generalization of the usually waveguide array is zigzag array. Due to zigzag configuration there are interactions between both nearest and next nearest neighboring waveguides exist. The system of evolution equations for coupled waves has the steady state solution describing the electromagnetic pulse running in the array. Numerical simulation demonstrates robustness of these solitary waves.
Bulletin of the Russian Academy of Sciences: Physics, 2021
Bulletin of the Russian Academy of Sciences: Physics, 2020
Abstract The spin moment of a surface wave propagating along the interface between a dielectric a... more Abstract The spin moment of a surface wave propagating along the interface between a dielectric and a topological insulator is considered. The vector components of a spin moment form a discrete set that is a consequence of the discreteness of the topological number characterizing the topological insulator.
Quantum Electronics, 2017
The guided waves of a symmetric planar waveguide formed by an isotropic dielectric placed in a hy... more The guided waves of a symmetric planar waveguide formed by an isotropic dielectric placed in a hyperbolic medium and having a cubic-nonlinear response are studied theoretically. The optical axis of the hyperbolic medium is directed along the normal to the interfaces between the media. If the permittivity of the waveguide core exceeds the main permittivity for an extraordinary wave in the hyperbolic medium, then each TM mode is characterised by two cutoff frequencies. Dispersion relations for these modes are found in the case of focusing and defocusing core media. The number of the modes possible at a given frequency depends on the radiation intensity. It is shown that zero values of the mode propagation constants are possible in the waveguide, which corresponds to the formation of a standing wave between the boundaries of the waveguide. In addition, in the case of a defocusing waveguide layer, such stopped modes can be obtained with increasing field intensity. The dependences of the propagation constant and the width of the transverse distribution of the mode field on the radiation intensity are found and analysed.
EPJ Web of Conferences, 2015
Electromagnetic field scattering on a 2D array of rf-SQUIDs is considered. We show that the scatt... more Electromagnetic field scattering on a 2D array of rf-SQUIDs is considered. We show that the scattering changes for large amplitudes of the incident electromagnetic wave; above a critical amplitude, two different refraction states occur (bistability). In particular, for these two states, the transmitted wave polarization and angle of refraction are different. One could then switch the direction of propagation of the electromagnetic wave and its polarization with a "thin film", whose thickness is much smaller than the wavelength.
Nonlinear Optical Waves, 1999
Three main processes determine the features of optical phenomena. The first is the dynamics of el... more Three main processes determine the features of optical phenomena. The first is the dynamics of elementary radiators (atoms, molecules, excitons etc.) interacting with light. The second is the emission of light by elementary radiators. The third is the evolution of light waves within the medium under the influence of dispersion, diffraction, nonlinear compression and parametric wave interaction. Essential features of radiator dynamics and emission of light are brightly displayed in coherent optical transients such as free induction decay, optical nutation and various echo phenomena. The favourable condition of their formation is a resonant propagation of an ultrashort light pulses through such thin medium where dispersion and other processes inherent to wave propagation are inessential. In this case coherent transients exhibit the properties directly connected with medium structure. This circumstance is very attractive for spectroscopy especially for investigations of relaxation. The theoretical analysis of coherent transients becomes fairly simple for optically thin medium when the framework of a given field approximation in Maxwell-Bloch equations is valid. This approximation ignores the reaction of the medium to the passing light pulses. In spite of this simplicity coherent transients represent an important large class of nonlinear optical phenomena. This chapter is devoted to the description of the underlying main principles of coherent transients.
Journal of the Optical Society of America B, 2012
We have investigated the modulation instability (MI) in a nonlinear optical coupler using a gener... more We have investigated the modulation instability (MI) in a nonlinear optical coupler using a generalized model describing the pulse propagation of a waveguiding structure composed of two adjacent waveguides. The model consists of a nonlinear tunnel-coupled structure consisting of right-and left-handed media. The optical coupler considered here includes a local saturable nonlinear refractive index. In particular, we discuss the impact of the saturable nonlinearity for the MI of plane waves and formation of spatial solitons. The results show that MI can exist not only in the normal group velocity dispersion (GVD) regime but also in the normal GVD regime in the nonlinear positive-negative index coupler in the presence of saturable nonlinearity. The saturable nonlinearity can increase/decrease the number of sidebands or shift the existing sidebands. The maximum value of the MI gain, as well as its bandwidth, has been also affected by the saturable nonlinearity. Moreover, the saturable nonlinearity may influence considerably the number of wave trains induced by MI.
Journal of Experimental and Theoretical Physics, 1995
Collapse (self-compression over a finite time) of a solitary wave is studied. The process is desc... more Collapse (self-compression over a finite time) of a solitary wave is studied. The process is described by a one-dimensional nonlinear Schroedinger equation, in which terms corresponding to damping and fifth-order nonlinearity are included. Numerical solution of a system of equations for the width, amplitude, and degree of modulation reveals that the dissipation can suppress collapse if it is strong enough. Analytical expressions for the threshold values of the linear and nonlinear absorption coefficients are found by means of qualitative arguments. 23 refs., 5 figs.
Journal of Physics: Conference Series, Aug 1, 2016
In a model which describes asymmetric oppositely directed nonlinear waveguide coupler it was obse... more In a model which describes asymmetric oppositely directed nonlinear waveguide coupler it was observed in the numerical simulation a phenomenon of solitary wave formation from the input constant continuous wave set at the entrance of a waveguide with negative index of refraction. Threshold value of the amplitude of the constant continuous wave, which defines the condition of appearance of the first solitary wave, decreases with increasing of the parameter of nonlinearity. The period of solitary wave formation decreases with increasing of the continuum wave amplitude.
Optics and Spectroscopy, 2019
The Drude–Lorentz model, which makes it possible to describe a nonlinear response of a dielectric... more The Drude–Lorentz model, which makes it possible to describe a nonlinear response of a dielectric or conducting medium, can be suited for the description of nonlinear nonresonant responses of some exotic media: topological insulators, a Weil semimetal, or a Dirac metal. A generalized Drude–Lorentz model and its simplified version, in which topological effects are taken into account to a minimum extent, are presented. As an example of application of the simplified model, the second-order nonlinear conductivity is derived, which is responsible for the second harmonic generation and the effect of optical rectification. It is shown that the ratio of the topological conductivity to the ordinary linear conductivity contains constants that are proportional to the fine structure constant and the axion field gradient.
Bulletin of the Russian Academy of Sciences: Physics, 2018
Electromagnetic waves propagating along the waveguides forming a rhombic one-dimensional lattice ... more Electromagnetic waves propagating along the waveguides forming a rhombic one-dimensional lattice are considered. Two waveguides that are part of the unit cell are assumed to be made of negative-index material, while the third waveguide from the same array is composed of material with a positive refractive index and has cubic nonlinearity. The equations of tunneling-coupled solitary waves spreading in each waveguide are solved. Unlike discrete solitons, the waves are localized on the axis of waveguides, and the maximum position moves uniformly along the waveguides.
The effects are observed of propagation of an ultimately short (in one or several oscillation) el... more The effects are observed of propagation of an ultimately short (in one or several oscillation) electromagnetic pulse in a medium whose resonance transition characterized both by diagonal and non-diagonal matrix elements of dipole operator. The Maxwell-Bloch set of equation is employed without the approximation of slowly varying amplitudes. The analog of MacCall and Hahn area theorem is discussed corresponding to the process of the initial ultimately short pulse break up into subpulses. A novel solution is found in the form of a stable solitary bipolar signal, whose pulse area is not zero- non-zero breather.
The propagation of solitary waves in a Bragg grating formed by an array of thin nanostructured di... more The propagation of solitary waves in a Bragg grating formed by an array of thin nanostructured dielectric films is considered. A system of equations of Maxwell–Duffing type, describing forward- and backward-propagating waves in such a grating, is derived. Exact solitary wave solutions are found, analyzed, and compared with the results of direct numerical simulations. 1
We analyze the interaction of an electromagnetic spike (one cycle) with a thin layer of ferroelec... more We analyze the interaction of an electromagnetic spike (one cycle) with a thin layer of ferroelectric medium with two equilibrium states. The model is the set of Maxwell equations coupled to the undamped LandauKhalatnikov equation, where we do not assume slowly varying envelopes.
Optics and Spectroscopy, 2021
Based on the semiclassical description of the dynamics of electrons in topological media, the gyr... more Based on the semiclassical description of the dynamics of electrons in topological media, the gyrotropic properties of which are determined by a nonzero Berry curvature, a phenomenological model is proposed that allows one to consider some nonlinear optical processes—the generation of the third harmonic and the intensity dependent rotation of the wave polarization vector. The third-order nonlinear susceptibilities are determined, which determine the interaction of waves with allowance for the rotation of their polarization vector. Gyrotropy manifests itself in the dependence of the efficiency of conversion to the harmonic on the circular polarization of radiation, which can be used to measure the parameters of these media.
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Papers by Andrei I . Maimistov