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arXiv · 1208.0735

Scaling of the Rényi entropies in gapped quantum spin systems: Entanglement-driven order beyond symmetry breaking

S. M. Giampaolo·S. Montangero·F. Dell'Anno·S. De Siena·F. Illuminati
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Abstract

We investigate the scaling of the Rényi $α$-entropies in one-dimensional gapped quantum spin models. We show that the block entropies with $α> 2$ violate the area law monotonicity and exhibit damped oscillations. Depending on the existence of a factorized ground state, the oscillatory behavior occurs either below factorization or it extends indefinitely. The anomalous scaling corresponds to an entanglement-driven order that is independent of ground-state degeneracy and is revealed by a nonlocal order parameter defined as the sum of the single-copy entanglement over all blocks.

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S. M. Giampaolo, S. Montangero, F. Dell'Anno, S. De Siena, F. Illuminati. 2012-08-03. Scaling of the Rényi entropies in gapped quantum spin systems: Entanglement-driven order beyond symmetry breaking. https://arxiv.org/abs/1208.0735

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