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arXiv · 0807.2529

Enhancing the Detection of Natural Thermal Entanglement with Disorder

Jenny Hide·Wonmin Son·Vlatko Vedral
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Abstract

Physical systems have some degree of disorder present in them. We discuss how to treat natural, thermal entanglement in any random macroscopic system from which a thermodynamic witness bounded by a constant can be found. We propose that functional many-body perturbation theory be applied to allow either a quenched or an annealed average over the disorder to be taken. We find when considering the example of an XX Heisenberg spin chain with a random coupling strength, that the region of natural entanglement detected by both witnesses can be enhanced by the disorder.

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BibTeXRIS

Jenny Hide, Wonmin Son, Vlatko Vedral. 2009-02-09. Enhancing the Detection of Natural Thermal Entanglement with Disorder. https://doi.org/10.1103/physrevlett.102.100503

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