Origin of heavy-fermion behavior inCeCu2Si2

Abstract

We report the theoretical analysis of electron spectroscopy data for the heavy-fermion superconductor ${\mathrm{CeCu}}_2$ ${\mathrm{Si}}_2$, using the impurity Anderson Hamiltonian applied to the Ce 4f electrons. A good description of the spectra for ${\mathrm{CeCu}}_2$ ${\mathrm{Si}}_2$ is obtained, using rescaled ab initio hybridization matrix elements. The spectra are generally consistent with a Kondo Fermi-liquid description of this material. Near trivalence and a very small Kondo temperature are controlled more by hybridization of Ce 4f to Si and Cu s/p than to Cu 3d states.