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Scaling of Entanglement close to a Quantum Phase Transitions

A. Osterloh·L. Amico·G. Falci·R. Fazio
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Abstract

In this Letter we discuss the entanglement near a quantum phase transition by analyzing the properties of the concurrence for a class of exactly solvable models in one dimension. We find that entanglement can be classified in the framework of scaling theory. Further, we reveal a profound difference between classical correlations and the non-local quantum correlation, entanglement: the correlation length diverges at the phase transition, whereas entanglement in general remains short ranged.

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A. Osterloh, L. Amico, G. Falci, R. Fazio. 2002-04-16. Scaling of Entanglement close to a Quantum Phase Transitions. https://doi.org/10.1038/416608a

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