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arXiv · 1405.7250

Fate of the false Mott-Hubbard transition in two dimensions

T. Schäfer·F. Geles·D. Rost·G. Rohringer·E. Arrigoni·K. Held·N. Blümer·M. Aichhorn·A. Toschi
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Abstract

We have studied the impact of non-local electronic correlations at all length scales on the Mott-Hubbard metal-insulator transition in the unfrustrated two-dimensional Hubbard model. Combining dynamical vertex approximation, lattice quantum Monte-Carlo and variational cluster approximation, we demonstrate that scattering at long-range fluctuations, i.e., Slater-like paramagnons, opens a spectral gap at weak-to-intermediate coupling -- irrespectively of the preformation of localized or short-ranged magnetic moments. This is the reason, why the two-dimensional Hubbard model is insulating at low enough temperatures for any (finite) interaction and no Mott-Hubbard transition is observed.

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T. Schäfer, F. Geles, D. Rost, G. Rohringer, E. Arrigoni, K. Held, N. Blümer, M. Aichhorn, A. Toschi. 2014-12-11. Fate of the false Mott-Hubbard transition in two dimensions. https://doi.org/10.1103/physrevb.91.125109

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