Proposal for a cumulant-based Bell test for mesoscopic junctions

TL;DR

This paper proposes a cumulant-based Bell test for mesoscopic junctions that detects entanglement through higher-order quantum correlations, avoiding the need for single charge detection.

Contribution

It introduces a novel Bell test using fourth-order cumulants to identify entanglement in solid state systems without relying on single charge measurements.

Findings

Classical interpretation of second-order correlations is demonstrated.

A new inequality involving fourth-order cumulants is derived.

Method enables entanglement detection in mesoscopic transport setups.

Abstract

The creation and detection of entanglement in solid state electronics is of fundamental importance for quantum information processing. We prove that second-order quantum correlations can be always interpreted classically and propose a general test of entanglement based on the violation of a classically derived inequality for continuous variables by fourth-order quantum correlation functions. Our scheme provides a way to prove the existence of entanglement in a mesoscopic transport setup by measuring higher order cumulants without requiring the additional assumption of a single charge detection