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arXiv · 1912.01260

Ferromagnetic spin correlations in the two-dimensional Hubbard model

Philipp Werner·Xi Chen·Emanuel Gull
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Abstract

We analyze the dynamical nearest-neighbor and next-nearest-neighbor spin correlations in the 4-site and 8-site dynamical cluster approximation to the two-dimensional Hubbard model. Focusing on the robustness of these correlations at long imaginary times, we reveal enhanced ferromagnetic correlations on the lattice diagonal, consistent with the emergence of composite spin-1 moments at a temperature scale that essentially coincides with the pseudo-gap temperature $T^*$. We discuss these results in the context of the spin-freezing theory of unconventional superconductivity.

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Philipp Werner, Xi Chen, Emanuel Gull. 2019-12-03. Ferromagnetic spin correlations in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevresearch.2.023037

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