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Ferromagnetism in Hubbard Models

Hal Tasaki
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Abstract

We present the first rigorous examples of non-singular Hubbard models which exhibit ferromagnetism at zero temperature. The models are defined in arbitrary dimensions, and are characterized by finite-ranged hoppings, dispersive bands, and finite on-site Coulomb interaction U. The picture, which goes back to Heisenberg, that sufficiently large Coulomb interaction can revert Pauli paramagnetism into ferromagnetism has finally been confirmed in concrete examples.

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Hal Tasaki. 1997-08-18. Ferromagnetism in Hubbard Models. https://doi.org/10.1103/physrevlett.75.4678

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