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arXiv · 1912.00365

Tighter constraints of multiqubit entanglement for negativity

Long-Mei Yang·Bin Chen·Shao-Ming Fei·Zhi-Xi Wang
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Abstract

We provide a characterization of multiqubit entanglement monogamy and polygamy constraints in terms of negativity. Using the square of convex-roof extended negativity (SCREN) and the Hamming weight of the binary vector related to the distribution of subsystems proposed in Kim (Phys Rev A 97: 012334, 2018), we provide a new class of monogamy inequalities of multiqubit entanglement based on the $α$th power of SCREN for $α\geq1$ and polygamy inequalities for $0\leqα\leq1$ in terms of squared convex-roof extended negativity of assistance (SCRENoA). For the case $α<0$, we give the corresponding polygamy and monogamy relations for SCREN and SCRENoA, respectively. We also show that these new inequalities give rise to tighter constraints than the existing ones.

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Long-Mei Yang, Bin Chen, Shao-Ming Fei, Zhi-Xi Wang. 2019-12-01. Tighter constraints of multiqubit entanglement for negativity. https://doi.org/10.1007/s11128-019-2513-1

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