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Information × Registration Number 0218U002356, 0113U002479 , R & D reports Title Collective effects in superconductive and magnetic systems, as well as in quantum superfluids. popup.stage_title Head Pashitskii E.A., Registration Date 16-02-2018 Organization Institute of physics NASU popup.description2 Effects of the collective dynamics of quasiparticle and vortex states in various quantum and classical systems ranging from microscopic to cosmological scales are theoretically investigated. New physical results are obtained: it is shown that the nonmonotonic dependencies of the critical temperature of superconducting phase transition versus Cooper pair density observed in La2-xSrxCuO4 layered crystals are explainable in the framework of the BCS model provided the mechanism of superconductivity is governed by current carriers' interaction with both acoustic plasmons and phonons; in the framework of the critical state model the definition as well as the calculation method are introduced for the "generalized susceptibility" of the system "superconductor - pick-up coil", which bears practical significance for the contactless measurements of the critical current density; the theoretical analysis of the superfast switching of the microparticles' magnetic moment with times of about 10 picoseconds is carried out to demonstrate that such switching times are attainable through longitudinal magnetization dynamics due to the quantum spin shortening; the analysis of the topological magnetic solitons in spin nematics has reviled the possibility of their utilization as the basis for the terahertz-range spintronic nanogenerators; a new model is proposed to describe the generation of the giant MHD vortices in solar chromosphere, with the vortex' azimuthal plasma velocities exponentially growing in time up to the speed of sound; in the framework of the model of the isotropic Bose liquid with Bose-condensate suppressed due to the strong collective interaction between particles, the phonon spectrum of such a liquid is shown to obey the decay dispersion low, in complete accord with the experimental data on neutron scattering in superfluid helium; it is shown that the phase transition of the first kind driven by the change in the scalar curvature of the 4-dimensional space-time could be the cause of the Big Bang in the early Universe; the model of the inflationary expansion is proposed for the early Universe filled with nonlinear scalar field and non-ideal Fermi-gas with short-range repulsion between the particles. Product Description popup.authors Галкіна Олена Григорівна Пашицький Ернст Анатолійович Пентегов Всеволод Ігорович Семенов Олексій Володимирович popup.nrat_date 2020-04-02 Close