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arXiv · 2512.24057

A new entanglement measure based on the total concurrence

Dong-Ping Xuan·Zhong-Xi Shen·Wen Zhou·Zhi-Xi Wang·Shao-Ming Fei
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Abstract

Quantum entanglement is a crucial resource in quantum information processing, advancing quantum technologies. The greater the uncertainty in subsystems' pure states, the stronger the quantum entanglement between them. From the dual form of $q$-concurrence ($q\geq 2$) we introduce the total concurrence. A bona fide measure of quantum entanglement is introduced, the $\mathcal{C}^{t}_q$-concurrence ($q \geq 2$), which is based on the total concurrence. Analytical lower bounds for the $\mathcal{C}^{t}_q$-concurrence are derived. In addition, an analytical expression is derived for the $\mathcal{C}^{t}_q$-concurrence in the cases of isotropic and Werner states. Furthermore, the monogamy relations that the $\mathcal{C}^{t}_q$-concurrence satisfies for qubit systems are examined. Additionally, based on the parameterized $\alpha$-concurrence and its complementary dual, the $\mathcal{C}^{t}_\alpha$-concurrence $(0\leq\alpha\leq\frac{1}{2})$ is also proposed.

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Dong-Ping Xuan, Zhong-Xi Shen, Wen Zhou, Zhi-Xi Wang, Shao-Ming Fei. 2025-12-30. A new entanglement measure based on the total concurrence. https://doi.org/10.1002/qute.202500149

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