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arXiv · 2502.18446

Entanglement and distillation from symmetric positive maps

Albert Rico
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Abstract

Recently, a toolkit of highly symmetric techniques employing matrix inequalities has been developed to detect entanglement in various ways. Here we unifiedly explain in detail these methods, and expand them to a new family of positive maps with further detection capabilities. In the simplest case, we generalize the reduction map to detect more generic states using both multiple copies and local filters. Through the Choi-Jamio{\l}kowski isomorphism, this family of maps leads to a construction of multipartite entanglement witnesses. Discussions and examples are provided regarding the detection of states with local positive partial transposition and the use of multiple copies.

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Albert Rico. 2025-02-25. Entanglement and distillation from symmetric positive maps. https://doi.org/10.1103/yz86-vqk9

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