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arXiv · 2608.29049

Eigenvalues of multipartite entanglement witnesses

Nalan Wang·Lin Chen
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Abstract

We investigate various properties of multipartite block-positive operators, decomposable EWs (DEWs), and non-decomposable EWs. We provide a necessary and sufficient condition to construct a special DEW using the multipartite GHZ state. For multipartite DEW, we explicitly characterize the supremum and infimum of maximum and minimum eigenvalues, as well as the trace of its square. We also derive other results concerning NDEW, eigenvalues of $2 \times n$ EWs and the corresponding physical implications. Furthermore, we investigate the tightness of inequalities of these eigenvalues with examples.

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Nalan Wang, Lin Chen. 2026-08-29. Eigenvalues of multipartite entanglement witnesses. https://arxiv.org/abs/2608.29049

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