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Effects of doping on spin correlations in the periodic Anderson model

J. Bonca·J. E. Gubernatis
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Abstract

We studied the effects of hole doping on spin correlations in the periodic Anderson model, mainly at the full and three-quarters-full lower bands cases. In the full lower band case, strong anti-ferromagnetic correlations develop when the on-site repulsive interaction strength $U$ becomes comparable to the quasi-particle band width. In the three-quarters full case, a novel kind of spin correlation develops that is consistent with the resonance between a $(π,0)$ and a $(0,π)$ spin-density wave. In this state the spins on different sublattices appear uncorrelated. Hole doping away from the completely full case rapidly destroys the long-range anti-ferromagnetic correlations, in a manner reminiscent of the destruction of anti-ferromagnetism in the Hubbard model. In contrast to the Hubbard model, the doping does not shift the peak in the magnetic structure factor from the $(π,π)$ position. At dopings intermediate to the full and three-quarters full cases, only weak spin correlations exist.

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J. Bonca, J. E. Gubernatis. 1998-06-30. Effects of doping on spin correlations in the periodic Anderson model. https://doi.org/10.1103/physrevb.58.6992

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