arXiv:1511.08819 · Physical review. B./Physical review. B

Entanglement negativity in two-dimensional free lattice models

Viktor Eisler, Zoltán Zimborás

Published Mar 31, 2016• 72 citations

Abstract

We study the scaling properties of the ground-state entanglement between finite subsystems of infinite two-dimensional free lattice models, as measured by the logarithmic negativity. For adjacent regions with a common boundary, we observe that the negativity follows a strict area law for a lattice of harmonic oscillators, whereas for fermionic hopping models the numerical results indicate a multiplicative logarithmic correction. In this latter case we conjecture a formula for the prefactor of the area-law violating term, which is entirely determined by the geometries of the Fermi surface and the boundary between the subsystems. The conjecture is tested against numerical results and a good agreement is found.

DOI: 10.1103/physrevb.93.115148

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