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arXiv · 2606.31010

Estimating the concurrence for quantum states via symmetric measurements

Hao-Fan Wang·Wen Zhou·Lin Chen·Shao-Ming Fei
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Abstract

We derive improved lower bounds of concurrence induced by symmetric measurements, which retains experimental feasibility without state tomography. More importantly, we resolve a related inequality conjecture, which implies that numerous previous results based on symmetric measurements are strictly stronger than the one based on realignment. In addition, we also present a lower bound of genuine tripartite entanglement concurrence based on symmetric measurements.

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Hao-Fan Wang, Wen Zhou, Lin Chen, Shao-Ming Fei. 2026-06-30. Estimating the concurrence for quantum states via symmetric measurements. https://arxiv.org/abs/2606.31010

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