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arXiv · 1612.03646

Breakdown of the Nagaoka phase at finite doping

Ilya Ivantsov·Alvaro Ferraz·Evgenii Kochetov
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Abstract

The Nagaoka ($U=\infty$) limit of the Hubbard model on a square lattice is mapped onto the itinerant-localized Kondo model at infinitely strong coupling. Such a model is well suited to perform quantum Monte Carlo (QMC) simulations to compute spin correlation functions. This model is shown to exhibit no short-range ferromagnetic (FM) spin correlations at any doping $\delta\ge 0.01$ and finite temperature, $T=0.1t$. Our simulations give no indication that there is a tendency towards ferromagnetic ordering in the ground state.

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Ilya Ivantsov, Alvaro Ferraz, Evgenii Kochetov. 2016-12-12. Breakdown of the Nagaoka phase at finite doping. https://doi.org/10.1103/physrevb.95.155115

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