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arXiv · 2007.10808

Constraint relation between steerability and concurrence for two-qubit states

Xiao-Gang Fan·Huan Yang·Fei Ming·Zhi-Yong Ding·Dong Wang·Liu Ye
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Abstract

Entanglement and steering are used to describe quantum inseparabilities. Steerable states form a strict subset of entangled states. A natural question arises concerning how much territory steerability occupies entanglement for a general two-qubit entangled state. In this work, we investigate the constraint relation between steerability and concurrence by using two kinds of evolutionary states and randomly generated two-qubit states. By combining the theoretical and numerical proofs, we obtain the upper and lower boundaries of steerability. And the lower boundary can be used as a sufficient criterion for steering detection. Futhermore, we consider a special kind of mixed state transformed by performing an arbitrary unitary operation on Werner-like state, and propose a sufficient steering criterion described by concurrence and purity.

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Xiao-Gang Fan, Huan Yang, Fei Ming, Zhi-Yong Ding, Dong Wang, Liu Ye. 2020-07-18. Constraint relation between steerability and concurrence for two-qubit states. https://doi.org/10.1002/andp.202100098

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