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arXiv · 2312.14275

Two-site reduced density matrix from one- and two-particle Green's functions

Gergő Roósz·Anna Kauch·Frederic Bippus·Daniel Wieser·Karsten Held
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Abstract

Strongly correlated electron systems are challenging to calculate, and entanglement in such systems is not widely analyzed. We present an approach that can be used as a post-processing step for calculating the two-site reduced density matrix and from it entanglement measures such as the mutual information and entanglement negativity. Input is only the one- and two-particle Green's function which is the output of numerous many-body methods. As an illustration, we present results for a toy model, the Hubbard model on a $2\times2$ cluster and a $6$ site ring.

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Gergő Roósz, Anna Kauch, Frederic Bippus, Daniel Wieser, Karsten Held. 2023-12-21. Two-site reduced density matrix from one- and two-particle Green's functions. https://arxiv.org/abs/2312.14275

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