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arXiv · 0710.2095

Entanglement in spatially inhomogeneous many-fermion systems

V. V. França·K. Capelle
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Abstract

We investigate entanglement of strongly interacting fermions in spatially inhomogeneous environments. To quantify entanglement in the presence of spatial inhomogeneity, we propose a local-density approximation (LDA) to the entanglement entropy, and a nested LDA scheme to evaluate the entanglement entropy on inhomogeneous density profiles. These ideas are applied to models of electrons in superlattice structures with different modulation patterns, electrons in a metallic wire in the presence of impurities, and phase-separated states in harmonically confined many-fermion systems, such as electrons in quantum dots and atoms in optical traps. We find that the entanglement entropy of inhomogeneous systems is strikingly different from that of homogeneous systems.

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V. V. França, K. Capelle. 2008-01-17. Entanglement in spatially inhomogeneous many-fermion systems. https://doi.org/10.1103/physrevlett.100.070403

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