English

Does a large quantum Fisher information imply Bell correlations?

Quantum Physics 2019-05-03 v3

Abstract

The quantum Fisher information (QFI) of certain multipartite entangled quantum states is larger than what is reachable by separable states, providing a metrological advantage. Are these nonclassical correlations strong enough to potentially violate a Bell inequality? Here, we present evidence from two examples. First, we discuss a Bell inequality designed for spin-squeezed states which is violated only by quantum states with a large QFI. Second, we relax a well-known lower bound on the QFI to find the Mermin Bell inequality as a special case. However, a fully general link between QFI and Bell correlations is still open.

Keywords

Cite

@article{arxiv.1810.01330,
  title  = {Does a large quantum Fisher information imply Bell correlations?},
  author = {Florian Fröwis and Matteo Fadel and Philipp Treutlein and Nicolas Gisin and Nicolas Brunner},
  journal= {arXiv preprint arXiv:1810.01330},
  year   = {2019}
}

Comments

4 pages, minor edits

R2 v1 2026-06-23T04:26:06.283Z