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Register a new userScaling of the Renyi entropies in gapped quantum spin systems: Entanglement-driven order beyond symmetry breaking
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Fabrizio Illuminati
Publication date
2012
fields
Physics
and research's language is
English
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We investigate the scaling of the Renyi $alpha$-entropies in one-dimensional gapped quantum spin models. We show that the block entropies with $alpha > 2$ 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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