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Absence of a Slater Transition in The Two-Dimensional Hubbard Model

S. Moukouri·M. Jarrell
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Abstract

We present well-controlled results on the metal to insulator transition (MIT) within the paramagnetic solution of the dynamical cluster approximation (DCA) in the two-dimensional Hubbard model at half-filling. In the strong coupling regime, a local picture describes the properties of the model; there is a large charge gap $Δ\approx U$. In the weak-coupling regime, we find a symbiosis of short-range antiferromagnetic correlations and moment formation cause a gap to open at finite temperature as in one dimension. Hence, this excludes the mechanism of the MIT proposed by Slater long ago.

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S. Moukouri, M. Jarrell. 2000-11-14. Absence of a Slater Transition in The Two-Dimensional Hubbard Model. https://doi.org/10.1103/physrevlett.87.167010

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