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arXiv · 2409.17689

Entanglement witnesses with local partial ordering

Joshua Carlo A. Casapao·Eric A. Galapon
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Abstract

We investigate a class of entanglement witnesses where each witness is formulated as a difference of two product observables. These observables are decomposable into positive semidefinite local operators that obey a partial ordering rule defined over all their possible expectation values. We provide a framework to construct these entanglement witnesses along with some examples. We also discuss methods to improve them both linearly and nonlinearly.

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Joshua Carlo A. Casapao, Eric A. Galapon. 2024-09-26. Entanglement witnesses with local partial ordering. https://arxiv.org/abs/2409.17689

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