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arXiv · 2303.10389

Entanglement as the cross-symmetric part of quantum discord

Chunhe Xiong·Sunho Kim·Asutosh Kumar·Zeyu Chen·Minghui Wu·Junde Wu
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Abstract

In this paper, we show that the minimal quantum discord over "cross-symmetric" state extensions is an entanglement monotone. In particular, we show that the minimal Bures distance of discord over cross-symmetric extensions is equivalent to the Bures distance of entanglement. At last, we refute a long-held but unstated convention that only contractive distances can be used to construct entanglement monotones by showing that the entanglement quantifier induced by the Hilbert-Schmidt distance, which is not contractive under quantum operations, is also an entanglement monotone.

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Chunhe Xiong, Sunho Kim, Asutosh Kumar, Zeyu Chen, Minghui Wu, Junde Wu. 2023-03-18. Entanglement as the cross-symmetric part of quantum discord. https://doi.org/10.1016/j.physleta.2023.129030

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