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arXiv · 2506.09780

Two-site entanglement in the two-dimensional Hubbard model

Frederic Bippus·Anna Kauch·Gergő Roósz·Christian Mayrhofer·Fakher Assaad·Karsten Held
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Abstract

The study of entanglement in strongly correlated electron systems typically requires knowledge of the reduced density matrix. Here, we apply the parquet dynamical vertex approximation to study the two-site reduced density matrix at varying distance, in the Hubbard model at weak coupling. This allows us to investigate the spatial structure of entanglement in dependence of interaction strength, electron filling, and temperature. We compare results from different entanglement measures, and benchmark against quantum Monte Carlo.

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Frederic Bippus, Anna Kauch, Gergő Roósz, Christian Mayrhofer, Fakher Assaad, Karsten Held. 2025-06-11. Two-site entanglement in the two-dimensional Hubbard model. https://doi.org/10.1103/81gy-zz9l

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