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Concurrence in collective models

J. Vidal
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Abstract

We review the entanglement properties in collective models and their relationship with quantum phase transitions. Focusing on the concurrence which characterizes the two-spin entanglement, we show that for first-order transition, this quantity is singular but continuous at the transition point, contrary to the common belief. We also propose a conjecture for the concurrence of arbitrary symmetric states which connects it with a recently proposed criterion for bipartite entanglement.

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J. Vidal. 2006-06-14. Concurrence in collective models. https://doi.org/10.1103/physreva.73.062318

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