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arXiv · 2007.15908

Entanglement correction due to local interactions in many-body systems

Yevheniia Cheipesh·Lorenzo Cevolani·Stefan Kehrein
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Abstract

The correction to the area law for the bipartite min-entanglement entropy of weakly and locally interacting fermions is calculated based on a perturbative extension of the flow equation holography method. Explicit calculations for the one- and two-dimensional case (and similarly for higher dimensions) show that the leading correction to the entanglement entropy of non-interacting fermions up to $U^2$ in the interaction strength does not change the scaling, but only affects the pre-factor of the leading logarithmic term multiplying it by the quasiparticle residue. A term sub-leading to the area law is also present. It is proportional to $U^2$ in the interaction strength and scales linearly with the system size.

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Yevheniia Cheipesh, Lorenzo Cevolani, Stefan Kehrein. 2020-07-31. Entanglement correction due to local interactions in many-body systems. https://arxiv.org/abs/2007.15908

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