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arXiv · 1901.09151

Critical Entanglement for the Half-Filled Extended Hubbard Model

Jon Spalding·Shan-Wen Tsai·David K Campbell
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Abstract

We study the ground state of the one-dimensional extended Hubbard model at half-filling using the entanglement entropy calculated by Density Matrix Renormalization Group (DMRG) techniques. We apply a novel curve fitting and scaling method to accurately identify a $2^{nd}$ order critical point as well as a Berezinskii-Kosterlitz-Thouless (BKT) critical point. Using open boundary conditions and medium-sized lattices with very small truncation errors, we are able to achieve similar accuracy to previous authors. We also report observations of finite-size and boundary effects that can be remedied with careful pinning.

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Jon Spalding, Shan-Wen Tsai, David K Campbell. 2019-01-26. Critical Entanglement for the Half-Filled Extended Hubbard Model. https://doi.org/10.1103/physrevb.99.195445

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