PAL'-VAL' P. Low-temperature mechanisms of dislocation acoustic relaxations in crystals.

Objects: bee metals, semimetals, Zr, Si. Goals: installation of elementary mechanisms of dislocation dynamics at low temperatures. Methods: acoustic spectroscopy methods. New results: the concept of dislocation mobility in the Peierls relief is refined. A new concept of unusual effect of the phonon and electron viscosity on the thermoactivated motion of dislocation kinks is developed. A method of consideration of a statistical character of dislocation structure evolutions is suggested. The dislocation -impurity dynamic interactions are investigated in detail. The notions of influence of dislocations on phase transformations as well as of the dislocation dynamics near the critical points are extended. A consistent relation between dynamic behaviour of a crystal, as an element of low-temperature acoustic devices, and dislocation processes in its volume is proposed.