Solitons in normal Fermi liquid

Abstract

To be based on the new quantum kinetic equation of Fermi particles, which recently was derived by N.L. Tsintsadze and L.N. Tsintsadze, a general quantum dispersion equation for almost ideal Fermi gas is derived and studied for some interesting cases. Here we consider only pair interactions between particles and we used energy expression derived by V.M. Galitski in the ordinary perturbation theory, which involves only the scattering amplitude. New effect that we have shown is that novel quantum term (Madelung term) in the kinetic equation leads to the formation of rarefaction solitary waves in neutral Fermi liquid. Furthermore, attraction and repulsion between particles have tendency to change rarefaction solitary wave speed and shape: Attraction between particles increases rarefaction soliton speed and amplitude, repulsion decreases soliton speed and amplitude.