Dicke subsystems are entangled

Szilárd Szalay; Péter Nyári

doi:10.22331/q-2025-11-06-1908

Dicke subsystems are entangled

Szilárd Szalay^1,2,3 and Péter Nyári^1,4

¹Department of Theoretical Solid State Physics, HUN-REN Wigner Research Centre for Physics, Budapest, Hungary
²Department of Theoretical Physics, University of the Basque Country UPV/EHU, Bilbao, Spain
³EHU Quantum Center, University of the Basque Country UPV/EHU, Leioa, Biscay, Spain
⁴Department of Physics of Complex Systems, Eötvös Loránd University, Budapest, Hungary

Published:	2025-11-06, volume 9, page 1908
Editor:	Felix Huber
Eprint:	arXiv:2502.18574v3
Doi:	https://doi.org/10.22331/q-2025-11-06-1908
Citation:	Quantum 9, 1908 (2025).

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Abstract

We show that all reduced states of nonproduct symmetric Dicke states of arbitrary number of qudits are genuinely multipartite entangled, and of nonpositive partial transpose with respect to any subsystem.

► BibTeX data

@article{Szalay2025dickesubsystemsare,
  doi = {10.22331/q-2025-11-06-1908},
  url = {https://doi.org/10.22331/q-2025-11-06-1908},
  title = {Dicke subsystems are entangled},
  author = {Szalay, Szil{\'{a}}rd and Ny{\'{a}}ri, P{\'{e}}ter},
  journal = {{Quantum}},
  issn = {2521-327X},
  publisher = {{Verein zur F{\"{o}}rderung des Open Access Publizierens in den Quantenwissenschaften}},
  volume = {9},
  pages = {1908},
  month = nov,
  year = {2025}
}

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[3] Kiara Hansenne, Rui Qu, Lisa T. Weinbrenner, Carlos de Gois, Haifei Wang, Yang Ming, Zhengning Yang, Paweł Horodecki, Weibo Gao, and Otfried Gühne, "Optimal Overlapping Tomography", Physical Review Letters 135 6, 060801 (2025).

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