Stefano Cusumano, Lorenzo Campos Venuti, Simone Cepollaro, Gianluca Esposito, Daniele Iannotti, Barbara Jasser, Jovan Odavić, Michele Viscardi, Alioscia Hamma (Apr 07 2025).

Abstract: We study quantitatively the interplay between entanglement and non-stabilizer resources in violating the CHSH inequalities. We show that, while non-stabilizer resources are necessary, they must have a specific structure, namely they need to be both asymmetric and (surprisingly) local. We employ stabilizer entropy (SE) to quantify the non-stabilizer resources involved and the probability of violation given the resources. We show how spectral quantities related to the flatness of entanglement spectrum and its relationship with non-local SE affect the CHSH inequality. Finally, we utilize these results - together with tools from representation theory - to construct a systematic way of building ensembles of states with higher probability of violation.

Arxiv: https://arxiv.org/abs/2504.03351