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arXiv · 2411.07803

Tighter superadditivity relations for $l_{1}$-norm coherence measure

Kang-Kang Yang·Zhong-Xi Shen·Zhi-Xi Wang·Shao-Ming Fei
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Abstract

Quantum coherence serves as a crucial physical resource, with its quantification emerging as a focal point in contemporary research. Superadditivity constitutes one of the most fundamental attributes in characterizing the coherence distribution in multipartite quantum systems. In this paper, we provide a way to derive tighter superadditivity inequalities of $l_1$-norm coherence measure for arbitrary multiqubit states. We present a category of superadditivity relations related to the $\alpha$-th ($\alpha\geqslant 2$) power of $l_{1}$-norm coherence $C_{l_{1}}$ under certain conditions. Our results are better than existing ones and are illustrated in detail with examples.

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Kang-Kang Yang, Zhong-Xi Shen, Zhi-Xi Wang, Shao-Ming Fei. 2024-11-12. Tighter superadditivity relations for $l_{1}$-norm coherence measure. https://doi.org/10.1142/s0219749924500266

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