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The Kondo-Hubbard model at half-filling

J. Perez-Conde·F. Bouis·P. Pfeuty
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Abstract

We have analyzed the antiferromagnetic (J>0) Kondo-Hubbard lattice with the band at half-filling by means of a perturbative approach in the strong coupling limit, the small parameter is an arbitrary tight-binding band. The results are valid for any band shape and any dimension. We have obtained the energies of elementary charge and spin excitations as well as the magnetic correlations in order to elucidate the magnetic and charge behavior of the Kondo lattice at half-filling. Finally, we have briefly analyzed the ferromagnetic case (J<0), which is shown to be equivalent to an effective antiferromagnetic Heisenberg model.

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J. Perez-Conde, F. Bouis, P. Pfeuty. 1998-08-18. The Kondo-Hubbard model at half-filling. https://doi.org/10.1016/s0921-4526(98)01172-7

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