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Information × Registration Number 0121U108126, ( 0226U001827  ) R & D request Title Kinetic phenomena and nanosystems in the volume and on the surface of condensed helium Head Sokolov Sviatoslav S., д.ф.-м.н. Registration Date 10-02-2021 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description1 The aim of the work is to study the fundamental properties of the superfluid and solid phases of helium, which are due to the creation, development and evolution of neutral and charged nanostructures in such phases. The liquid and solid phases of helium are the most striking example of a neutral condensed medium in which the combination of thermodynamic and kinetic properties is provided by quantum effects on a macroscopic scale. This leads to the fact that it is in helium one can possible to observe and study a number of phenomena that are fundamentally new. Thus, we can research the process of appearance and development of quantum turbulence, which occurs during the formation of a tangle of quantized vortices - one of the attributes of superfluid helium. When studying the solid phases of helium, it is possible to identify the influence of point and extended defect structures in crystalline helium on the nature of mass transfer and diffusion processes that such a transition accompany. The placement of solid helium in a limited geometry leads to an unusual phase composition of helium and limited diffusion processes. Due to the properties of the free surface of liquid helium, quasi-two-dimensional and quasi-one-dimensional systems of surface electrons appear above it, which have two or one degree of freedom for gradual motion, and have unique transport properties and phase composition. One can hope that during the project performance new concepts can be formulated in line with the fundamental physics of low temperatures regarding the characteristics of vortex nanosystems in superfluid 4He and 3He - 4He solutions and the development of quantum turbulence and cavitation in such media, mass transfer and kinetics of long and point defects in solid helium, phase transitions, and carrier transport in low-dimensional surface electron systems. popup.nrat_date 2024-12-09 Close