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Information × Registration Number 0213U001602, 0112U004182 , R & D reports Title Construction of the teory that provides the synthesis of thermodynamics and quantum theory for describing quantum-thermal fluctuations in the equilibrium state of objects with a stochastic environment-the first year of the project. popup.stage_title Head Baryakhtar, Registration Date 09-01-2013 Organization Institute of magnetism of NASU popup.description2 The possibility of description of the system states "the object surrounded by the arbitrary vacuum" on the basis of the wave function is realized in the present research. The using of quantum language becomes especially noticeable in situations when thermal and quantum fluctuations occur simultaneously. It is shown that the most worthy candidates for the role of the quantum analogue of thermal states are correlated-coherent states. It is found that consistent explanation of quantum thermal effects in the conditions of the object equilibrium state with a stochastic environment at any temperature is only possible on the basis of the aggregation of correlated-coherent states. It is shown that for the anisotropic sigma-model with an easy-plane anisotropy an abnormal behaviour of damping of quasi-particles (magnons) takes place. For gapless elementary excitations with linear dispersion law at small wave vectors, the damping decrement is proportional of the forth power of frequency (not quadratic over frequency, as for standard goldstone quasiparticles, for example, for purely isotropic sigmamodel), that can noted as a "supergoldstone" behavior of damping. As usually, the damping decrement for the second branch of quasi-particles, having finite activation, has finite value at small wave vectors. But this damping decrement has peculiarities too, namely, at low temperatures it has a power dependence on the temperature, and not contains the standard exponentially small temperature multiplier. Product Description popup.authors Іванов Б.О. Бар'яхтар В.Г. Горобець Ю.І. Грановський В.Б. Данилевич О.Г. Данилевич О.Й. Черненко М.А. popup.nrat_date 2020-04-02 Close