Effect of sharp structure in the electronic density of states on the electron-phonon coupling in highTc, superconductors

Abstract

Abstract The evidence for sharp structure in the electronic density of states N(e) of certain classes of high T c superconductors is based on the normal state temperature dependence of the spin susceptibility x, electronic specific-heat coefficient γ, electrical resistivity p, and nuclear spin-lattice relaxation rate 1/T1. Model calculations of x, γ, p, and T1 in the rigid N(ε) approximation and of x and γ for a temperature dependent N(ε) are presented for V3Ga and V3Si. The model calculations have been used to calculate the explicit temperature dependence of the electron mass enhancement and the renormalized electronic specific heat coefficient. The temperature dependence of the dielectric screening, which can have an important effect on renormalizing the phonon frequencies at low temperatures, is also discussed.