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arXiv · 2401.15593

Multipartite entanglement serves as a faithful detector for quantum phase transitions

Y. C. Li·Y. H. Zhou·Y. Zhang·Y. K. Bai·H. Q. Lin
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Abstract

We investigate quantum phase transitions in various spin chain systems using the multipartite entanglement measure $\tau_{SEF}$ based on the monogamy inequality of squared entanglement of formation. Our results demonstrate that $\tau_{SEF}$ is more effective and reliable than bipartite entanglement or bipartite correlation measures such as entanglement of formation, von Neumann entropy, and quantum discord in characterizing quantum phase transitions. $\tau_{SEF}$ not only detects critical points that may go unnoticed by other detectors but also avoids the issue of singularity at non-critical points encountered by other measures. Furthermore, by applying $\tau_{SEF}$, we have obtained the phase diagram for the XY spin chain with three and four interactions and discovered a new quantum phase.

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Y. C. Li, Y. H. Zhou, Y. Zhang, Y. K. Bai, H. Q. Lin. 2024-01-28. Multipartite entanglement serves as a faithful detector for quantum phase transitions. https://arxiv.org/abs/2401.15593

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