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arXiv · 0806.2598

Observable estimation of entanglement for arbitrary finite-dimensional mixed states

Cheng-Jie Zhang·Yan-Xiao Gong·Yong-Sheng Zhang·Guang-Can Guo
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Abstract

We present observable upper bounds of squared concurrence, which are the dual inequalities of the observable lower bounds introduced in [F. Mintert and A. Buchleitner, Phys. Rev. Lett. 98, 140505 (2007)] and [L. Aolita, A. Buchleitner and F. Mintert, Phys. Rev. A 78, 022308 (2008)]. These bounds can be used to estimate entanglement for arbitrary experimental unknown finite-dimensional states by few experimental measurements on a twofold copy $ρ\otimesρ$ of the mixed states. Furthermore, the degree of mixing for a mixed state and some properties of the linear entropy also have certain relations with its upper and lower bounds of squared concurrence.

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Cheng-Jie Zhang, Yan-Xiao Gong, Yong-Sheng Zhang, Guang-Can Guo. 2008-10-10. Observable estimation of entanglement for arbitrary finite-dimensional mixed states. https://doi.org/10.1103/physreva.78.042308

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