EFFECTS OF DOPING ON SPIN CORRELATIONS IN THE PERIODIC ANDERSON MODEL

We studied the effects of hole doping on spin correlations in the two- dimensional periodic Anderson model, mainly at the full and three-quar ters-full lower bands cases. In the full lower band case, strong antif erromagnetic correlations develop when the on-site repulsive interacti on strength U becomes comparable to the quasiparticle bandwidth. In th e three-quarters full case, a kind of spin correlation develops that i s consistent with the resonance between a (pi,0) and a (0, pi) spin-de nsity wave. In this state the spins on different sublattices appear un correlated. Hole doping away from the completely full case rapidly des troys the long-range antiferromagnetic correlations, in a manner remin iscent of the destruction of antiferromagnetism in the Hubbard model. In contrast to the Hubbard model, the doping does not shift the peak i n the magnetic structure factor from the ( pi, pi) position. At doping s intermediate to the full and three-quarters full cases, only weak sp in correlations exist.