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arXiv · 0709.3766

Entanglement detection beyond the cross-norm or realignment criterion

Cheng-Jie Zhang·Yong-Sheng Zhang·Shun Zhang·Guang-Can Guo
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Abstract

Separability problem, to decide whether a given state is entangled or not, is a fundamental problem in quantum information theory. We propose a powerful and computationally simple separability criterion, which allows us to detect the entanglement of many bound entangled states. The criterion is strictly stronger than the dV criterion, the computable cross-norm or realignment criterion and its optimal nonlinear entanglement witnesses. Furthermore, this criterion can be generalized to an analogue of permutation separability criteria in the even-partite systems.

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Cheng-Jie Zhang, Yong-Sheng Zhang, Shun Zhang, Guang-Can Guo. 2008-06-03. Entanglement detection beyond the cross-norm or realignment criterion. https://doi.org/10.1103/physreva.77.060301

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