arXiv:1105.4756 · Physical Review Letters
Entanglement Entropy of One-Dimensional Gases
Pasquale Calabrese, Mihail Mintchev, Ettore Vicari
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.