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arXiv · 2411.07065

Entanglement witnesses and separability criteria based on generalized equiangular tight frames

Katarzyna Siudzińska
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Abstract

We use operators from generalized equiangular measurements to construct positive maps. Their positivity follows from the inequality for indices of coincidence corresponding to few equiangular tight frames. These maps give rise to entanglement witnesses, which include as special cases many important classes considered in the literature. Additionally, we introduce separability criteria based on the correlation matrix and analyze them for various types of measurements.

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Katarzyna Siudzińska. 2024-11-11. Entanglement witnesses and separability criteria based on generalized equiangular tight frames. https://arxiv.org/abs/2411.07065

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