Steering bound entangled states: A counterexample to the stronger Peres conjecture

TL;DR

This paper presents a method to generate bound entangled states that can still demonstrate quantum steering, disproving the stronger Peres conjecture and enabling semi-device independent certification of weak entanglement.

Contribution

It introduces a systematic way to produce bound entangled states capable of steering, challenging previous assumptions about their limitations and relations to the Peres conjecture.

Findings

Bound entangled states can exhibit steering.

Disproves the stronger Peres conjecture.

Weak entanglement can be certified semi-device independently.

Abstract

Quantum correlations are at the heart of many applications in quantum information science and, at the same time, they form the basis for discussions about genuine quantum effects and their difference to classical physics. On one hand, entanglement theory provides the tools to quantify correlations in information processing and many results have been obtained to discriminate useful entanglement, which can be distilled to a pure form, from bound entanglement, being of limited use in many applications. On the other hand, for discriminating quantum phenomena from their classical counterparts, Schr\"odinger and Bell introduced the notions of steering and local hidden variable models. We provide a method to generate systematically bound entangled quantum states which can still be used for steering and therefore to rule out local hidden state models. This sheds light on the relations between the various views on quantum correlations and disproves a widespread conjecture known as the stronger Peres conjecture. For practical applications, it implies that even the weakest form of entanglement can be certified in a semi-device independent way.