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arXiv · 1904.10529

Approximate expression for the ground-state energy of the two- and three-dimensional Hubbard model at arbitrary filling obtained from dimensional scaling

Luana N. O. Vilela·Klaus Capelle·Luiz N. Oliveira·Vivaldo L. Campo
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Abstract

We generalize the linear discrete dimensional scaling approach for the repulsive Hubbard model to obtain a nonlinear scaling relation that yields accurate approximations to the ground-state energy in both two and three dimensions, as judged by comparison to auxiliary-field quantum Monte Carlo (QMC) data. Predictions are made for the per-site ground-state energies in two and three dimensions for $n$ (filling factor) and $U$ (Coulomb interaction) values for which QMC data are currently unavailable.

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Luana N. O. Vilela, Klaus Capelle, Luiz N. Oliveira, Vivaldo L. Campo. 2019-04-23. Approximate expression for the ground-state energy of the two- and three-dimensional Hubbard model at arbitrary filling obtained from dimensional scaling. https://doi.org/10.1088/1361-648x%2Fab32ac

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