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arXiv · 1105.4756

The entanglement entropy of one-dimensional gases

Pasquale Calabrese·Mihail Mintchev·Ettore Vicari
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Abstract

We introduce a systematic framework to calculate the bipartite entanglement entropy of a spatial subsystem in a one-dimensional quantum gas which can be mapped into a noninteracting fermion system. To show the wide range of applicability of the proposed formalism, we use it for the calculation of the entanglement in the eigenstates of periodic systems, in a gas confined by boundaries or external potentials, in junctions of quantum wires and in a time-dependent parabolic potential.

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cond-mat.stat-mechcond-mat.quant-gasquant-ph

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Pasquale Calabrese, Mihail Mintchev, Ettore Vicari. 2011-06-13. The entanglement entropy of one-dimensional gases. https://doi.org/10.1103/physrevlett.107.020601

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