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arXiv · 1912.01807

Mutually unbiased measurement based entanglement witnesses

Tao Li·Le-Min Lai·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

We study entanglement witness and present a construction of entanglement witnesses in terms of the mutually unbiased measurements (MUMs). These witnesses include the entanglement witnesses constructed from mutually unbiased bases (MUBs) as a special case. Comparing with the dimension dependence of MUBs, the witnesses can be always constructed from a complete set of $d+1$ MUMs for any dimension $d$. We show that our witness can detect entanglement better than previous separability criterion given also by MUMs. And the approach can be experimentally implemented.

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Tao Li, Le-Min Lai, Shao-Ming Fei, Zhi-Xi Wang. 2019-12-04. Mutually unbiased measurement based entanglement witnesses. https://doi.org/10.1007/s10773-019-04263-9

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