EXCITATION OF ZERO SOUND-WAVES AND QUASI-WAVES IN METALS WITH WEAK FERMI-LIQUID INTERACTION

In terms of a single model three types of fast waves are considered, which are excited in the Fermi-liquid of the metal by a sound impulse. The conditions are specified, which are required to form waves of the zero sound. In particular, il is shown that in the case of a weak Fermi-liquid interaction the zero sound is formed at distances from the metal surface which considerably exceed its wavelength. It is also shown that the ballistic quasi-wave known in the model of the Fermi-gas is significantly influenced by the Fermi-liquid interaction. At omegatau << 1 the quasi-wave competes with the non-equilibrium concentrations wave of various types of carriers.