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arXiv · 1803.11065

Optimization of ultrafine entanglement witnesses

Shu-Qian Shen·Ti-Run Xu·Shao-Ming Fei·Xianqing Li-Jost·Ming Li
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Abstract

The ultrafine entanglement witness, introduced in [F. Shahandeh, M. Ringbauer, J.C. Loredo, and T.C. Ralph, Phys. Rev. Lett. \textbf{118}, 110502 (2017)], can seamlessly and easily improve any standard entanglement witness. In this paper, by combining the constraint and the test operators, we rotate the hyperplane determined by the test operator and improve further the original ultrafine entanglement witness. In particular, we present a series of new ultrafine entanglement witnesses, which not only can detect entangled states that the original ultrafine entanglement witnesses cannot detect, but also have the merits that the original ultrafine entanglement witnesses have.

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Shu-Qian Shen, Ti-Run Xu, Shao-Ming Fei, Xianqing Li-Jost, Ming Li. 2018-03-29. Optimization of ultrafine entanglement witnesses. https://doi.org/10.1103/physreva.97.032343

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