Syrnykov Y. The kinetics process at phase separation of weak solid mixtures 4He in 3He at ultralow temperatures

Object: phase separation of weak solid mixtures 4He in 3He. Goals: the establishing of nucleation mechanisms under phase separation, of the influence of surface under phase separation, of the connection between kinetics of phase separation and diffusion processes in solid mixtures of 4He in 3He, of vacancy nanocluster kinetic properties. Method: precise pressure measurements. New results: for the fist time, the systematic quantities data are obtained on kinetics of phase separation in solid mixtures of 4He in 3He. It is shown that characteristics time of phase separation can be presented as a sum of two times - diffusion and surface ones. The concentration dependence of diffusion coefficient of 4He in 3He is established. It is shown that experimental data on phase separation kinetics in helium samples of high quality are well described within frames of the theory of homogeneous nucleation. It is shown that the processes of growth and dissolution of vacancy nanoclusters of 4He are strongly asymmetric.