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arXiv · 1903.09947

Thermodynamics of the metal-insulator transition in the extended Hubbard model

M. Schüler·E. G. C. P. van Loon·M. I. Katsnelson·T. O. Wehling
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Abstract

In contrast to the Hubbard model, the extended Hubbard model, which additionally accounts for non-local interactions, lacks systemic studies of thermodynamic properties especially across the metal-insulator transition. Using a variational principle, we perform such a systematic study and describe how non-local interactions screen local correlations differently in the Fermi-liquid and in the insulator. The thermodynamics reveal that non-local interactions are at least in parts responsible for first-order metal-insulator transitions in real materials.

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M. Schüler, E. G. C. P. van Loon, M. I. Katsnelson, T. O. Wehling. 2019-03-24. Thermodynamics of the metal-insulator transition in the extended Hubbard model. https://doi.org/10.21468/scipostphys.6.6.067

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