Changes to the t-J Model From Inclusion of Two-Site Nearest-Neighbor Coulomb Interactions

Tao Sun

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arXiv · 1704.08420

Changes to the t-J Model From Inclusion of Two-Site Nearest-Neighbor Coulomb Interactions

Tao Sun

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Abstract

To date, the Hubbard model and its strong coupling limit, the t-J model, serve as the canonical model for strongly correlated electron systems in solids. Approximating the Coulomb interaction by only the on-site term (Hubbard U-term), however, may not be sufficient to describe the essential physics of interacting electron systems. We develop a more complete model in which all the next leading order terms besides the on-site term are retained. Moreover, we discuss how the inclusion of these neglected interaction terms in the Hubbard model changes the t-J model.

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Tao Sun. 2017-04-27. Changes to the t-J Model From Inclusion of Two-Site Nearest-Neighbor Coulomb Interactions. https://arxiv.org/abs/1704.08420

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