The Ground State of the Anderson Model. Variational Approach

Abstract

AbstractThe ground state of the Anderson model is examined by means of the variational trial function which emphasizes interaction between the impurity electron and the electrons on the Fermi surface. Both, the number of electrons and the phase shift of the conduction electrons at the Fermi level are found to be continuous functions of the model parameters. The results reduce to the exact solutions at both the atomic and the strongly interacting system limits. They are compared with the Anderson solution in the Hartree‐Fock approximation, and the meaning of the local moment in both approaches is discussed. The local moment is shown to cause strong decrease of the impurity resistivity under increasing magnetic field at low temperature.