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arXiv:0910.0706 · Physical Review B

Entanglement entropy of two disjoint blocks in critical Ising models

Vincenzo Alba, Luca Tagliacozzo, Pasquale Calabrese

Published Feb 22, 2010• 136 citations
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Abstract

We study the scaling of the R\'enyi and entanglement entropy of two disjoint blocks of critical Ising models as function of their sizes and separations. We present analytic results based on conformal field theory that are quantitatively checked in numerical simulations of both the quantum spin chain and the classical two-dimensional Ising model. Theoretical results match the ones obtained from numerical simulations only after taking properly into account the corrections induced by the finite length of the blocks to their leading scaling behavior.

DOI
10.1103/physrevb.81.060411

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