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arXiv · 2406.19080

G_q-concurrence and entanglement constraints in multiqubit systems

Hui Li·Ting Gao·Fengli Yan
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Abstract

In this paper, we introduce a category of one-parameter bipartite entanglement quantifiers, termed $G_q$-concurrence ($q>1$), and show rigorously that they satisfy all the axiomatic conditions of an entanglement measure and can be considered as a generalization of concurrence. In addition, we establish an analytic formula relating $G_q$-concurrence to concurrence for $1<q\leq2$ in two-qubit systems. Furthermore, the polygamy relation is presented based on the $G_q$-concurrence of assistance in multiqubit systems. As far as $G_q$-concurrence ($1<q\leq2$) itself is concerned, however, it does not obey the monogamy relation, but we prove that the square of $G_q$-concurrence does. By means of this monogamy inequality, we construct a set of entanglement indicators that can detect genuinely multiqubit entangled states even when the tangle loses its efficacy.

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Hui Li, Ting Gao, Fengli Yan. 2024-06-27. G_q-concurrence and entanglement constraints in multiqubit systems. https://arxiv.org/abs/2406.19080

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