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arXiv:1012.4270 · Europhysics Letters (EPL)

Ground-state factorization and correlations with broken symmetry

Bruno Tomasello, Davide Rossini, Alioscia Hamma, Luigi Amico A

Published Sep 23, 2011• 63 citations
arXivHTMLPDF

Abstract

We show how the phenomenon of factorization in a quantum many-body system is of collective nature. To this aim we study the quantum discord Q in the one-dimensional XY model in a transverse field. We analyze the behavior of Q at both the critical point and at the non-critical factorizing field. The factorization is found to be governed by an exponential scaling law for Q . We also address the thermal effects fanning out from the anomalies occurring at zero temperature. Close to the quantum phase transition, Q exhibits a finite-temperature crossover with universal scaling behavior, while the factorization phenomenon results in a non-trivial pattern of correlations present at low temperature.

DOI
10.1209/0295-5075/96/27002

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