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arXiv · 1901.08847

Characterizing multipartite entanglement classes via higher-dimensional embeddings

Christina Ritz·Cornelia Spee·Otfried Gühne
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Abstract

Witness operators are a central tool to detect entanglement or to distinguish among the different entanglement classes of multiparticle systems, which can be defined using stochastic local operations and classical communication (SLOCC). We show a one-to-one correspondence between general SLOCC witnesses and a class of entanglement witnesses in an extended Hilbert space. This relation can be used to derive SLOCC witnesses from criteria for full separability of quantum states; moreover, given SLOCC witness can be viewed as entanglement witnesses. As applications of this relation we discuss the calculation of overlaps between different SLOCC classes, and the SLOCC classification in $2\times 3\times 3$-dimensional systems.

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Christina Ritz, Cornelia Spee, Otfried Gühne. 2019-01-25. Characterizing multipartite entanglement classes via higher-dimensional embeddings. https://doi.org/10.1088/1751-8121/ab2f54

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