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arXiv · 1812.00205

Finer Distribution of Quantum Correlations among Multiqubit Systems

Zhi-Xiang Jin·Shao-Ming Fei
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Abstract

We study the distribution of quantum correlations characterized by monogamy relations in multipartite systems. By using the Hamming weight of the binary vectors associated with the subsystems, we establish a class of monogamy inequalities for multiqubit entanglement based on the $α$th ($α\geq 2$) power of concurrence, and a class of polygamy inequalities for multiqubit entanglement in terms of the $β$th ($0\leq β\leq2$) power of concurrence and concurrence of assistance. Moveover, we give the monogamy and polygamy inequalities for general quantum correlations. Application of these results to quantum correlations like squared convex-roof extended negativity (SCREN), entanglement of formation and Tsallis-$q$ entanglement gives rise to either tighter inequalities than the existing ones for some classes of quantum states or less restrictions on the quantum states. Detailed examples are presented.

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Zhi-Xiang Jin, Shao-Ming Fei. 2018-12-01. Finer Distribution of Quantum Correlations among Multiqubit Systems. https://doi.org/10.1007/s11128-018-2137-x

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