Nonlocality from Local Contextuality

Phys Rev Lett. 2016 Nov 25;117(22):220402. doi: 10.1103/PhysRevLett.117.220402. Epub 2016 Nov 23.

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 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.