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arXiv · 2004.02700

Stability of the enhanced area law of the entanglement entropy

Peter Müller·Ruth Schulte
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Abstract

We consider a multi-dimensional continuum Schr\"odinger operator which is given by a perturbation of the negative Laplacian by a compactly supported potential. We establish both an upper and a lower bound on the bipartite entanglement entropy of the ground state of the corresponding quasi-free Fermi gas. The bounds prove that the scaling behaviour of the entanglement entropy remains a logarithmically enhanced area law as in the unperturbed case of the free Fermi gas. The central idea for the upper bound is to use a limiting absorption principle for such kinds of Schr\"odinger operators.

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Peter Müller, Ruth Schulte. 2020-04-06. Stability of the enhanced area law of the entanglement entropy. https://doi.org/10.1007/s00023-020-00961-x

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