Experimental generation of entanglement from classical correlations via non-unital local noise

TL;DR

This paper demonstrates experimentally how classical correlations can be transformed into quantum entanglement using non-unital local noise and a CNOT gate, showing entanglement generation in simple and complex quantum systems.

Contribution

It introduces a novel method of generating entanglement from classical correlations through non-unital local noise, validated by two different experimental setups.

Findings

Entanglement can be produced from classical correlations with non-unital noise.

Entanglement generation is proportional to the degree of introduced noise.

The scheme is robust against local unitaries by an adversary.

Abstract

We experimentally show how classical correlations can be turned into quantum entanglement, via the presence of non-unital local noise and the action of a CNOT gate. We first implement a simple two-qubit protocol in which entanglement production is not possible in the absence of local non-unital noise, while entanglement arises with the introduction of noise, and is proportional to the degree of noisiness. We then perform a more elaborate four-qubit experiment, by employing two hyperentangled photons initially carrying only classical correlations. We demonstrate a scheme where the entanglement is generated via local non-unital noise, with the advantage to be robust against local unitaries performed by an adversary.