Sharing Quantum Nonlocality in Star Network Scenarios

TL;DR

This paper investigates the sharing properties of quantum nonlocality in star network scenarios, revealing that network states exhibit stronger sharing abilities than traditional Bell nonlocality, with implications for quantum foundations and security.

Contribution

It provides the first comprehensive analysis of nonlocality sharing in star network quantum states, highlighting differences from Bell nonlocality sharing under various measurements.

Findings

Network quantum states have stronger sharing ability than Bell nonlocality.

Sharing ability under unilateral measurements is similar to Bell nonlocality.

Sharing ability under bilateral measurements differs from Bell nonlocality.

Abstract

The Bell nonlocality is closely related to the foundations of quantum physics and has significant applications to security questions in quantum key distributions. In recent years, the sharing ability of the Bell nonlocality has been extensively studied. The nonlocality of quantum network states is more complex. We first discuss the sharing ability of the simplest bilocality under unilateral or bilateral POVM measurements, and show that the nonlocality sharing ability of network quantum states under unilateral measurements is similar to the Bell nonlocality sharing ability, but different under bilateral measurements. For the star network scenarios, we present for the first time comprehensive results on the nonlocality sharing properties of quantum network states, for which the quantum nonlocality of the network quantum states has a stronger sharing ability than the Bell nonlocality.