Аннотация

The dynamical interaction of charged carriers and ions is considered for a transverse sound propagation in layered superconductors with open Fermi surfaces. The difference from conventional superconductors follows due to the new Pippard factors for quasi-two-dimensional materials. The transverse electric field could be neglected in high-T, superconductors because of small values of both the carrier plasma frequency and the carrier scattering lifetime. The sound attenuation depends strongly on an angle of a wave propagation with respect to layers. The dynamical change of a sound velocity is always positive for layered superconductors at low temperatures and could be negative only near the transition temperature. The used model for noneauilibrium carrier states could be important for the ultrasonic diagnostic technique.