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Information × Registration Number 0226U000559, (0122U001845) , R & D reports Title Kinetic, thermodynamic and magnetodynamic effects in multiparticle, quantum and mesoscopic systems popup.stage_title Дослідження динамічних станів, що виникають під дією лазерного імпульсу та отримання розв’язку часових рівнянь для квазічасток. Head Ivanov Boris O., Доктор фізико-математичних наукLos Viktor F., д.ф.-м.н. Registration Date 12-01-2026 Organization Institute of Magnetism NAS of Ukraine and MES of Ukraine popup.description1 The goal of the project is to develop mathematical methods for analysis of different nonlinear dynamics modes in antiferromagnetic and textured structures of spintronics and magnonics, deriving of completely closed evolution equations which describing the kinetics of a statistical operator for an arbitrary system of quantum particles, obtaining the solution of time wave equations and the Klein-Gordon equation, as well as a rigorous consideration of the tunneling process from a potential well. popup.description2 Specific properties of the domain walls dynamics of a ferrimagnet near the orbital magnetic moment compensation area have been studied: the transition to a non-stationary regime. This regime is accompanied by strong nonlinear dynamics of the internal magnetization, which covers a wide frequency range up to terahertz. This effect can be used to generate spin wave pulses with high frequencies and group velocities. It has been experimentally and theoretically demonstrated that nonlinear spin-wave dynamics can initiate an effective resonant interaction between non-resonant magnon modes in yttrium iron garnet disks. The spin wave frequencies and precession amplitudes in the two-layer Van der Waals antiferromagnet CrSBr under the action of external in-plane magnetic fields are investigated. The concept of Baryakhtar exchange relaxation that accurately accounting for the effects of longitudinal evolution of sublattice spins is applied to describe the spin dynamics of antiferromagnets for pure exchange interactions of spins. Some nontrivial features of the exchange spin evolution of highly nonlinear states are analyzed, including dynamically induced nonequivalence of sublattice spins and long-lasting spatially homogeneous spin oscillations with exchange frequencies. The magnetic properties of nanodisks placed inside or near a circular hole in a perpendicularly magnetized matrix of antidisks are studied. Three-dimensional topological charges (Hopf indices) were calculated for a special case of three-dimensional topological magnetic solitons - toroidal Hopfions in cylindrical and spherical ferromagnetic nanoparticles. A projection operator was obtained that exactly transforms the inhomogeneous generalized master NakajimanZwanzig equation for the corresponding part of the statistical operator of the system plus the reservoir, which contains a non-homogeneous irrelevant term and includes initial correlations, into a homogeneous equation. Product Description popup.authors Ihor V. Gerasimchuk Serhii O. Reshetniak Denys V. Slobodianiuk Elena V. Tartakovskaya Borys О. Ivanov Viktor F. Los Oleksiy K. Kolezhuk Vadym Kireev Roman V. Verba Roman R. Teslia Artem Bondarenko Oleksandr Galkin popup.nrat_date 2026-01-12 Close