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Entanglement versus chaos in disordered spin chains

L. F. Santos·G. Rigolin·C. O. Escobar
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Abstract

We use a Heisenberg spin-1/2 chain to investigate how chaos and localization may affect the entanglement of pairs of qubits. To measure how much entangled a pair is, we compute its concurrence, which is then analyzed in the delocalized/localized and in the chaotic/non-chaotic regimes. Our results indicate that chaos reduces entanglement and that entanglement decreases in the region of strong localization. In the transition region from a chaotic to a non-chaotic regime localization increases entanglement. We also show that entanglement is larger for strongly interacting qubits (nearest neighbors) than for weakly interacting qubits (next and next-next neighbors).

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L. F. Santos, G. Rigolin, C. O. Escobar. 2004-04-12. Entanglement versus chaos in disordered spin chains. https://doi.org/10.1103/physreva.69.042304

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