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arXiv · 1310.4477

Cumulative measure of correlation for multipartite quantum states

André L. Fonseca de Oliveira·Efrain Buksman·Jesús García López de Lacalle
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Abstract

The present article proposes a measure of correlation for multiqubit mixed states. The measure is defined recursively, accumulating the correlation of the subspaces, making it simple to calculate without using of regression. Unlike usual measures, the proposed measure is continuous additive and reflects the dimensionality of the state space, allowing to compare states with different dimensions. Examples show that the measure can signal critical points (CP) in the analysis of Quantum Phase Transitions in Heisenberg models.

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André L. Fonseca de Oliveira, Efrain Buksman, Jesús García López de Lacalle. 2013-10-16. Cumulative measure of correlation for multipartite quantum states. https://doi.org/10.1142/s0217979214500507

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