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arXiv · 1912.05076

Tighter generalized monogamy and polygamy relations for multiqubit systems

Zhi-Xiang Jin·Shao-Ming Fei
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Abstract

We present a different kind of monogamy and polygamy relations based on concurrence and concurrence of assistance for multiqubit systems. By relabeling the subsystems associated with different weights, a smaller upper bound of the $α$th ($0\leqα\leq2$) power of concurrence for multiqubit states is obtained. We also present tighter monogamy relations satisfied by the $α$th ($0\leqα\leq2$) power of concurrence for $N$-qubit pure states under the partition $AB$ and $C_1 . . . C_{N-2}$, as well as under the partition $ABC_1$ and $C_2\cdots C_{N-2}$. These inequalities give rise to the restrictions on entanglement distribution and the trade off of entanglement among the subsystems. Similar results are also derived for negativity.

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Zhi-Xiang Jin, Shao-Ming Fei. 2020-10-09. Tighter generalized monogamy and polygamy relations for multiqubit systems. https://doi.org/10.1007/s11128-019-2522-0

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