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arXiv · 0705.1832

Optimal entanglement witnesses based on local orthogonal observables

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

We show that the entanglement witnesses based on local orthogonal observables which are introduced in [S. Yu and N.-L. Liu, Phys. Rev. Lett. 95, 150504 (2005)] and [O. Gühne, M. Mechler, G. Tóth and P. Adam, Phys. Rev. A 74, 010301 (2006)] in linear and nonlinear forms can be optimized, respectively. As applications, we calculate the optimal nonlinear witnesses of pure bipartite states and show a lower bound on the I-concurrence of bipartite higher dimensional systems with our method.

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Cheng-Jie Zhang, Yong-Sheng Zhang, Shun Zhang, Guang-Can Guo. 2007-08-02. Optimal entanglement witnesses based on local orthogonal observables. https://doi.org/10.1103/physreva.76.012334

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