Genuine Activation of Quantum Nonlocality: Stronger Than Local Indistinguishability

TL;DR

This paper investigates the activation of stronger forms of quantum nonlocality beyond local indistinguishability, demonstrating that such nonlocal features can be activated from sets lacking these properties, with implications for quantum information tasks.

Contribution

It introduces the activation of stronger quantum nonlocality notions and shows how to convert locally distinguishable entangled states into genuinely entangled, irreducible sets.

Findings

Activated stronger nonlocality in quantum states.

Converted locally distinguishable states into irreducible entangled sets.

Demonstrated activation in multipartite entangled states.

Abstract

The structure of quantum theory assures the discrimination of any possible orthogonal set of states. However, the scenario becomes highly nontrivial in the limited measurement setting and leads to different classes of impossibility, viz., indistinguishability, unmarkability, irreducibility etc. These phenomena, often referred to as other nonlocal aspects of quantum theory, have utmost importance in the domain of secret sharing etc. It, therefore, becomes a pertinent question to distill/activate such behaviours from a set, apparently devoid of these nonlocal features and free from local redundancy. While the activation of local indisitinguishability in the sets of entangled states has recently been reported, other stronger notion of quantum nonlocality has yet not been inspected in the parlance of activation. Here, we explored all such stronger versions of nonlocality and affirmatively answered to activate each of them. We also find a locally distinguishable set of multipartite entangled states which can be converted with certainty to a nontrivial set of locally irreducible genuinely entangled states.