Quantum steering with bound entanglement

TL;DR

This paper demonstrates that bound entangled states, previously thought too weak for steering, can indeed enable quantum steering, impacting our understanding of entanglement's role in quantum information tasks.

Contribution

It shows that bound entanglement can produce quantum steering, revealing a new link between weak entanglement and nonlocality using entropic uncertainty relations.

Findings

Bound entangled states can lead to quantum steering.

Steering inequalities derived from entropic uncertainty relations are effective.

Implications for entanglement distillability and nonlocality are discussed.

Abstract

Quantum steering, loosely speaking the distribution of entanglement from an untrusted party, is a form of quantum nonlocality which is intermediate between entanglement and Bell nonlocality. Determining which states can be steered is important from a conceptual point of view, but also for applications, e.g. in quantum cryptography. Here we show that bound entanglement, although it represents the weakest form of entanglement, can nevertheless lead to quantum steering. This is done by noticing that steering inequalities can be derived from entropic uncertainty relations. Our result has implications on the connection between entanglement distillability and nonlocality, and shows that bound entangled states can be useful for information-theoretic tasks featuring an untrusted party.