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Nagaoka ferromagnetism in the two-dimensional infinite-U Hubbard model

Federico Becca·Sandro Sorella
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Abstract

We present different numerical calculations based on variational quantum Monte Carlo simulations supporting a ferromagnetic ground-state for finite and small hole densities in the two-dimensional infinite-$U$ Hubbard model. Moreover, by studying the energies of different total spin sectors, these calculations strongly suggest that the paramagnetic phase is unstable against a phase with a partial polarization for large hole densities $δ\sim 0.40$ with evidence for a second-order transition to the paramagnetic large doping phase.

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Federico Becca, Sandro Sorella. 2001-02-14. Nagaoka ferromagnetism in the two-dimensional infinite-U Hubbard model. https://doi.org/10.1103/physrevlett.86.3396

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