Generation and read-out of many-body Bell correlations with a probe qubit

TL;DR

This paper presents a simple method for generating and certifying many-body Bell correlations using a single probe qubit interacting with an N-qubit system, enabling efficient detection of complex quantum correlations.

Contribution

The authors introduce a versatile approach where a single qubit interaction creates and certifies many-body entanglement and Bell correlations, with the probe qubit extracting all relevant information.

Findings

Pairwise qubit interaction induces many-body quantum correlations.

Single-qubit measurements can reveal multi-partite entanglement.

Method enables rapid certification of non-classicality in complex systems.

Abstract

As demand for quantum technologies increases, so does the need to generate and classify non-classical correlations in complex many-body systems. We introduce a simple and versatile method for creating and certifying entanglement and many-body Bell correlations. This method relies on a single qubit interacting with an $N$-qubit system. We demonstrate that: (i) such pairwise interaction is sufficient to induce many-body quantum correlations, and (ii) the qubit can serve as a probe to extract all information about these correlations. Thus, single-qubit measurements reveal multi-partite entanglement and $N$-body Bell correlations, enabling the rapid and efficient certification of non-classicality in complex systems.