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arXiv:1405.7391 · Physical Review B

Improving entanglement and thermodynamic Rényi entropy measurements in quantum Monte Carlo

David J. Luitz, Xavier Plat, Nicolas Laflorencie, Fabien Alet

Published Sep 3, 2014• 59 citations
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Abstract

We present a method for improving measurements of the entanglement R\'enyi entropies in quantum Monte Carlo simulations by relating them with measurements of participation R\'enyi entropies. Exploiting the capability of building improved estimators for the latter makes it possible to obtain very good estimates for entanglement R\'enyi entropies. When considering a full system instead of a bipartition, the method can be further ameliorated, providing access to the thermodynamic R\'enyi entropies with high accuracy. We also explore a recently proposed method for the reconstruction of the entanglement spectrum from entanglement R\'enyi entropies and finally show how potential entanglement Hamiltonians may be tested for their validity using a comparison with thermal R\'enyi entropies.

DOI
10.1103/physrevb.90.125105

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