SYMMETRICAL PERIODIC ANDERSON MODEL IN INFINITE DIMENSIONS

The symmetric periodic Anderson model is studied in the limit of infinite spatial dimensions with an essentially exact quantum Monte Carlo method. As the temperature is lowered T<T0, the properties of the system cross over from those of a metal with a moderately heavy mass, to those of an insulator in which the one- and two-particle spectra develop gaps T0, where T0 is the Wilson Kondo scale. Whereas the quasiparticle gap T0 is indirect in momentum, the optical conductivity displays a much larger direct gap. T0 is much larger in the symmetric lattice than in the impurity problem with the same parameters. Depending upon the ratio of T0 to the Ruderman-Kittel-Kasuya-Yosida exchange energy, there is a transition to an antiferromagnetic state. In the paramagnetic state, the f-electron linear specific heat shows scaling with T/T0, whereas the f-electron contribution to the bulk susceptibility shows only a rough scaling with T/T0 with deviations that are consistent with the strength of the net ferromagnetic exchange. © 1995 The American Physical Society.