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arXiv · 0705.2521

Multipartite entanglement of superpositions

D. Cavalcanti·M. O. Terra Cunha·A. Acin
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Abstract

The entanglement of superpositions [Phys. Rev. Lett. 97, 100502 (2006)] is generalized to the multipartite scenario: an upper bound to the multipartite entanglement of a superposition is given in terms of the entanglement of the superposed states and the superposition coefficients. This bound is proven to be tight for a class of states composed by an arbitrary number of qubits. We also extend the result to a large family of quantifiers which includes the negativity, the robustness of entanglement, and the best separable approximation measure.

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D. Cavalcanti, M. O. Terra Cunha, A. Acin. 2007-05-22. Multipartite entanglement of superpositions. https://doi.org/10.1103/physreva.76.042329

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