All entangled pure quantum states violate the bilocality inequality
Quantum Physics
2021-04-21 v1
Abstract
The nature of quantum correlations in networks featuring independent sources of entanglement remains poorly understood. Here, focusing on the simplest network of entanglement swapping, we start a systematic characterization of the set of quantum states leading to violation of the so-called "bilocality" inequality. First, we show that all possible pairs of entangled pure states can violate the inequality. Next, we derive a general criterion for violation for arbitrary pairs of mixed two-qubit states. Notably, this reveals a strong connection between the CHSH Bell inequality and the bilocality inequality, namely that any entangled state violating CHSH also violates the bilocality inequality. We conclude with a list of open questions.
Keywords
Cite
@article{arxiv.1702.00333,
title = {All entangled pure quantum states violate the bilocality inequality},
author = {Nicolas Gisin and Quanxin Mei and Armin Tavakoli and Marc-Olivier Renou and Nicolas Brunner},
journal= {arXiv preprint arXiv:1702.00333},
year = {2021}
}