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arXiv · 0908.4214

Entanglement detection via tighter local uncertainty relations

Cheng-Jie Zhang·Hyunchul Nha·Yong-Sheng Zhang·Guang-Can Guo
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Abstract

We propose an entanglement criterion based on local uncertainty relations (LURs) in a stronger form than the original LUR criterion introduced in [H. F. Hofmann and S. Takeuchi, Phys. Rev. A \textbf{68}, 032103 (2003)]. Using arbitrarily chosen operators $\{\hat{A}_{k}\}$ and $\{\hat{B}_{k}\}$ of subsystems A and B, the tighter LUR criterion, which may be used not only for discrete variables but also for continuous variables, can detect more entangled states than the original criterion.

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Cheng-Jie Zhang, Hyunchul Nha, Yong-Sheng Zhang, Guang-Can Guo. 2009-08-28. Entanglement detection via tighter local uncertainty relations. https://doi.org/10.1103/physreva.81.012324

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