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arXiv · 1110.4108

Correlation tensor criteria for genuine multiqubit entanglement

Wieslaw Laskowski·Marcin Markiewicz·Tomasz Paterek·Marek Zukowski
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Abstract

We present a development of a geometric approach to entanglement indicators. The method is applied to detect genuine multiqubit entanglement. The criteria are given in form of non-linear conditions imposed on correlation tensors. Thus they involve directly observable quantities, and in some cases require only few specific measurements to find multiqubit entanglement. The non-linearity of each of the criteria allows detection of entanglement in wide classes of states. In contrast to entanglement witnesses, which in the space of Hermitian operators define a hyperplane, the new conditions define a geometric figure encapsulating the non-fully entangled states within it.

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Wieslaw Laskowski, Marcin Markiewicz, Tomasz Paterek, Marek Zukowski. 2011-12-12. Correlation tensor criteria for genuine multiqubit entanglement. https://doi.org/10.1103/physreva.84.062305

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