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arXiv · 1310.3089

Entanglement entropy in quasi-symmetric multi-qubit states

Zhi-Hua Li·An-Min Wang
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Abstract

We generalize the symmetric multi-qubit states to their q-analogs, whose basis vectors are identified with the q-Dicke states. We study the entanglement entropy in these states and find that entanglement is extruded towards certain regions of the system due to the inhomogeneity aroused by q-deformation. We also calculate entanglement entropy in ground states of a related q-deformed Lipkin-Meshkov-Glick model and show that the singularities of entanglement can correctly signify the quantum phase transition points for different strengths of q-deformation.

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Zhi-Hua Li, An-Min Wang. 2013-10-11. Entanglement entropy in quasi-symmetric multi-qubit states. https://arxiv.org/abs/1310.3089

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