All quantum states useful for teleportation are nonlocal resources

TL;DR

This paper establishes that all quantum states capable of teleportation are inherently nonlocal, linking quantum inseparability with Bell nonlocality and suggesting nonlocality might be a universal feature of useful entangled states.

Contribution

It proves that all entangled states useful for teleportation exhibit Bell nonlocality, connecting two fundamental quantum phenomena and leveraging super-activation of nonlocality.

Findings

All teleportation-useful entangled states are nonlocal.

Super-activation of nonlocality is a key mechanism.

Nonlocality might be a generic property of entangled states.

Abstract

Understanding the relation between the different forms of inseparability in quantum mechanics is a longstanding problem in the foundations of quantum theory and has implications for quantum information processing. Here we make progress in this direction by establishing a direct link between quantum teleportation and Bell nonlocality. In particular, we show that all entangled states which are useful for teleportation are nonlocal resources, i.e. lead to deterministic violation of Bell's inequality. Our result exploits the phenomenon of super-activation of quantum nonlocality, recently proved by Palazuelos, and suggests that the latter might in fact be generic.