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Vector solitons in coupled nonlinear Schrödinger equations with spatial stimulated scattering and inhomogeneous dispersion
Communications in Nonlinear Science and Numerical Simulation. 2018. Vol. 54. P. 13–20.
The dynamics of two-component solitons is studied, analytically and numerically, in the framework of a system of coupled extended nonlinear Schrödinger equations, which incorporate the cross-phase modulation, pseudo-stimulated-Raman-scattering (pseudo-SRS), cross-pseudo-SRS, and spatially inhomogeneous second-order dispersion (SOD). The system models co-propagation of electromagnetic waves with orthogonal polarizations in plasmas. It is shown that the soliton's wavenumber downshift, caused by pseudo-SRS, may be compensated by an upshift, induced by the inhomogeneous SOD, to produce stable stationary two-component solitons. The corresponding approximate analytical solutions for stable solitons are found. Analytical results are well confirmed by their numerical counterparts. Further, the evolution of inputs composed of spatially even and odd components is investigated by means of systematic simulations, which reveal three different outcomes: formation of a breather which keeps opposite parities of the components; splitting into a pair of separating vector solitons; and spreading of the weak odd component into a small-amplitude pedestal with an embedded dark soliton.
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English
Avdeev R., Zaitseva Y., Mediterranean Journal of Mathematics 2026 Vol. 23 No. 7 Article 224
We provide an infinite series of commutative finite-dimensional Gorenstein local algebras A_n for n ≥ 2. We give an elementary proof that the maximal ideal of every algebra A_n possesses a one-dimensional subspace that is different from the socle and invariant under the automorphism group of A_n. The latter implies that the algebras A_n fail ...
Added: October 17, 2026
Gordin V. A., Efremenko D., Boundary-Layer Meteorology 2026 Vol. 192 No. 51
An inverse problem of reconstructing the turbulent exchange tensor from large archives of observed wind profiles within the Åkerblom–Ekman (A-E) model framework is investigated using high-vertical-resolution radiosonde observations. The reconstructed tensor provides improved agreement between modeled and observed wind profiles compared to classical formulations based on real turbulent exchange coefficient. Instead of the classical A-E ...
Added: October 16, 2026
Kuznetsov A. P., Sedova Y. V., Stankevich N., Chaos, Solitons and Fractals 2026 Vol. 213 No. 12 Article 119309
We analyze the interaction of a quasi-periodic subsystem, in which two-, three-, and four- frequency quasi-periodic oscillations are possible, with a chaotic subsystem. A discrete version is obtained via the Euler scheme from the corresponding flow model. The dynamics of individual subsystems are discussed, including quasi-periodic bifurcations of invariant tori and the occur rence of ...
Added: October 16, 2026
Aleksei Samarin, Nazarenko A., Nazarenko D. et al., Machine Learning and Knowledge Extraction 2026 Vol. 8 No. 10 Article 330
Automated microscopic image analysis is essential for quantitative microbiology, yet manual acquisition and generic recognition models struggle with morphological variability and scene artifacts. We address both ends of this pipeline. First, we present a low-cost, open-source acquisition system, based on an Arduino UNO R3 microcontroller and NEMA 17 stepper motors, that automates focusing, magnification, and ...
Added: October 14, 2026
Тукачев Н. В., Bataev V., Abramenkov A. et al., Computational and Theoretical Chemistry 2016 No. 1080 P. 23–32
Electronic state calculations, such as equilibrium geometry parameters, harmonic vibrational frequencies and potential barriers to conformational transitions (as well as conformer energy differences in excited states), using ab initio methods, such as MP2, CCSD(T), CASSCF, CASPT2 and MRCI, were carried out on the formamide molecule in the ground (S0) and the lowest excited singlet (S1) ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. А., Godunov I. А., Journal of Quantitative Spectroscopy and Radiative Transfer 2016 Vol. 177 P. 291–300
For conformers of the N-methylformamide (HCONHCH3) molecule, calculations of equilibrium geometry parameters, harmonic vibration frequencies, energy differences and potential barriers to conformational transitions were performed in the ground (S0) and lowest excited singlet (S1) and triplet (T1) electronic states. In the S0 state, the molecule exists in trans and cis stable conformations (having Cs symmetry). ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. А., Godunov I. А., Journal of Quantitative Spectroscopy and Radiative Transfer 2017 Vol. 192 P. 30–41
For acetamide molecule (CH3CONH2) in the ground (S0) and lowest excited singlet (S1) and triplet (T1) electronic states calculations of equilibrium geometry parameters, harmonic vibrational frequencies and barriers to conformational transitions (also conformer energy differences in excited states) using following ab initio methods: MP2, CCSD(T), CASSCF, CASPT2 and MRCI were performed. One-, two- and three-dimensional ...
Added: October 14, 2026
Тукачев Н. В., Bataev V. A., Godunov I. A., Computational and Theoretical Chemistry 2017 Vol. 1113 P. 82–93
Equilibrium geometry parameters, harmonic vibrational frequencies and barriers to conformational transitions and conformer energy differences for N-methylacetamide (CH3CONHCH3) molecule in S0, S1 and T1 electronic states were calculated in MP2 (S0) and CASPT2 (S1, T1) levels of theory. It is known that there are two planar (or effectively planar) conformers of N-methylacetamide in the ground ...
Added: October 14, 2026
Тукачев Н. В., Maslennikov D., Sosorev A. et al., The Journal of Physical Chemistry Letters 2019 Vol. 10 No. 12 P. 3232–3239
Conformational space of polyphenylenevinylene oligomers is systematically investigated computationally at energies relevant for room temperature dynamics in a solvent and in a solid state. Our calculations show that optimal oligomer structures are essentially planar. However, lack of a deep minimum at the planar geometry allows for large molecular deformations even at very low temperatures. At ...
Added: October 14, 2026
Тукачев Н. В., Akkuratov A., Kuznetsov I. et al., Synthetic Metals 2020 Vol. 259 Article 116231
Four new conjugated polymers based on benzodithiophene, thiophene and 2,1,3-benzothiadiazole or 5,6-difluoro-2,1,3-benzothiadiazole were synthesized and investigated as absorber materials for organic photovoltaics. The effect of (bi)thiophene π-spacers and fluorine substitution on the physicochemical and optoelectronic properties of the polymers was revealed and correlations were drawn with their electrical characteristics in organic solar cells. In particular, ...
Added: October 14, 2026
Тукачев Н. В., Nuraliev M., Parashchuk O. et al., Journal of Chemical Physics 2020 Vol. 153 No. 17 Article 174303
Electron–phonon interaction strongly affects and often limits charge transport in organic semiconductors (OSs). However, approaches to its experimental probing are still in their infancy. In this study, we probe the local electron–phonon interaction (quantified by the charge-transfer reorganization energy) in small-molecule OSs by means of Raman spectroscopy. Applying density functional theory calculations to four series ...
Added: October 14, 2026
Тукачев Н. В., Klimovich I., Prudnov F. et al., Dyes and Pigments 2021 Vol. 185 Article 108899
A series of ten conjugated polymers incorporating in their molecular frameworks extended DADAD building blocks with thiophene donor (D) and either benzotriazole, benzoxadiazole, benzothiadiazole, difluorobenzothiadiazole or quinoxaline acceptor (A) units were synthesized and characterized. The optoelectronic properties of new polymers were computed and experimentally investigated revealing a good relationship, which can guide further rational design ...
Added: October 14, 2026
Тукачев Н. В., Sosorev A., Parashchuk O. et al., Physical Chemistry Chemical Physics 2021 Vol. 23 No. 29 P. 15485–15491
Dynamic disorder manifested in fluctuations of charge transfer integrals considerably hinders charge transport in high-mobility organic semiconductors. Accordingly, strategies for suppression of the dynamic disorder are highly desirable. In this study, we suggest a novel promising strategy for suppression of dynamic disorder—tuning the molecular electrostatic potential. Specifically, we show that the intensities of the low-frequency ...
Added: October 14, 2026
Тукачев Н. В., González-Jiménez M., Ramakrishnan G. et al., Physical Chemistry Chemical Physics 2021 Vol. 23 No. 23 P. 13250–13260
Low-frequency vibrations play an essential role in biomolecular processes involving DNA such as gene expression, charge transfer, drug intercalation, and DNA–protein recognition. However, understanding the vibrational basis of these mechanisms relies on theoretical models due to the lack of experimental evidence. Here we present the low-frequency vibrational spectra of G-quadruplexes (structures formed by four strands ...
Added: October 14, 2026
Тукачев Н. В., González-Jiménez M., Barnard T. et al., Nature Communications 2023 Vol. 14 Article 215
A common feature of glasses is the “boson peak”, observed as an excess in the heat capacity over the crystal or as an additional peak in the terahertz vibrational spectrum. The microscopic origins of this peak are not well understood; the emergence of locally ordered structures has been put forward as a possible candidate. Here, ...
Added: October 14, 2026
Тукачев Н. В., Mali G., Tassieri M. et al., Journal of the American Chemical Society, USA 2023 Vol. 145 No. 48 P. 26061–26067
On supercooling a liquid, the viscosity rises rapidly until at the glass transition it vitrifies into an amorphous solid accompanied by a steep drop in the heat capacity. Therefore, a pure homogeneous liquid is not expected to display more than one glass transition. Here we show that a family of single-component homogeneous molecular liquids, titanium ...
Added: October 14, 2026
Тукачев Н. В., Dubinets N. O., Dominskiy D. I. et al., Optical Materials 2024 Vol. 157 No. 2 P. 1–8
Donor-acceptor molecules exhibiting TADF are in the heart of third-generation OLEDs. In this study, we apply (TD)DFT and multiscale modelling to assess the reliability of these approaches for prediction of the emission properties of carbazole-triazine (Cz-TRZ) based TADF luminophores. We found that a series of hybrid and doubly hybrid functionals reproduce the experimentally observed trend ...
Added: October 14, 2026
Тукачев Н. В., Su L., Zhou Y. et al., Polymer 2025 Vol. 326 Article 128336
As the power conversion efficiency (PCE) of organic photovoltaics (OPVs) approximates the 19 % threshold, wide bandgap (WBG) polythiophenes (PTs) have gained increasing attention due to their simple chemical structures and ease of synthesis, making them promising candidates for large-scale production. However, the benchmark polymer poly(3-hexylthiophene) (P3HT) is limited by its high-lying HOMO energy level, which ...
Added: October 14, 2026
Parkhomenko V., Kulikova S., Buzmakov A. V., Lobachevskii Journal of Mathematics 2026 Vol. 47 No. 6 P. 2979–2992
The stability of formal concepts and its generalization as robustness are considered in the paper. We use an approximation of stability in the form of Δ-measure for fast calculations. A computationally efficient method for calculating robustness based on subcontexts is presented. We also present a new method to analytically evaluate the number of preimages for ...
Added: October 14, 2026
Kuznetsov A. P., Sedova Y. V., Sataev I. R. et al., Mathematics and Computers in Simulation 2027 Vol. 2 P. 574–592
Universal bifurcation structures on the parameter plane of nonlinear systems, known as shrimps, are discussed. An overview of numerous examples from various fields of science is given. Shrimps are typical for both maps of different dimensions and flows. The varieties of shrimp are discussed and relevant examples are given. The similarity property on the parameter ...
Added: October 14, 2026
Dmitriev A., Kornilov V., Batienkov R., Lecture Notes in Civil Engineering 2026 Vol. 886 P. 249–255
Numerous studies have provided compelling evidence that the probability distribution of avalanche sizes follows a power law, and that 1/f noise is present in the stochastic dynamics of landslides. We present a theoretical explanation of these phenomena within the framework of self-organized criticality theory, proposing a discrete-time model in the form of a sandpile cellular ...
Added: October 13, 2026
Dmitriev A., Shulman I., Lebedev A., Studies in Computational Intelligence 2026 Vol. 1265 P. 266–273
A discrete-time model is presented for the self-organization of the X/Twitter social network to the edge of a phase transition, characterized by avalanche-like propagation of information in the network. The model is based on the analogy between the critical dynamics of the X social network and sandpile cellular automata with Manna rule on the Chung-Lu ...
Added: October 13, 2026
Arutyunov K., Kharitonov I. A., Petrosyants K. O., JETP Letters 2026 Vol. 124 No. 6 P. 1–16
Superconducting properties of metallic micro- and nanowires can be entirely different from those of bulk superconductors. Of particular interest is the nonequilibrium current-induced state of a quasi-one-dimensional superconducting channel. The most interesting phenomenon here is the stepped I–V characteristic, explained by a process known as phase slip center activation. If the origin of such step-like ...
Added: October 13, 2026
Levashev V., / Series arXiv "math". 2026. No. 2609.06010.
We prove that continuous A-bilinear pairings on the ring of Laurent series that are invariant under continuous automorphisms coincide, up to a constant, with the pairing given by the residue of a differential form over any commutative associative ring with identity. ...
Added: September 24, 2026