Nonlocality from local contextuality

TL;DR

This paper experimentally demonstrates that nonlocality can be derived from single-particle contextuality through two-particle correlations, linking two fundamental quantum resources and showing potential for dual quantum information applications.

Contribution

It provides the first experimental evidence that nonlocality can originate from local contextuality, bridging two key quantum phenomena and highlighting their combined utility.

Findings

Nonlocality can be generated from local contextuality.

Two-particle correlations do not violate Bell inequalities individually.

Quantum systems can be used for both computation and secure communication.

Abstract

We experimentally show that nonlocality can be produced from single-particle contextuality by using two-particle correlations which do not violate any Bell inequality by themselves. This demonstrates that nonlocality can come from an {\em a priori} different simpler phenomenon, and connects contextuality and nonlocality, the two critical resources for, respectively, quantum computation and secure communication. From the perspective of quantum information, our experiment constitutes a proof of principle that quantum systems can be used simultaneously for both quantum computation and secure communication.