Detection of non-Gaussian quantum correlations through measurement-after-interaction protocols

TL;DR

This paper demonstrates that measurement-after-interaction protocols can greatly improve the detection of non-Gaussian quantum correlations, including EPR steering and entanglement, with increased noise robustness using only linear measurements.

Contribution

It introduces a novel application of MAI protocols to detect non-Gaussian quantum correlations, surpassing previous methods in sensitivity and noise resilience.

Findings

Enhanced detection of EPR steering and mode entanglement in non-Gaussian states.

MAI protocols enable detection with linear measurements only.

Improved noise robustness in quantum correlation detection.

Abstract

Additional state evolutions performed before measurement, also called measurement-after-interactions (MAI) protocols, have shown a great potential for increasing the sensitivity of metrological scenarios. Here, we go beyond this result and show that MAI techniques can significantly enhance the detection capability of witnesses for quantum correlations. In particular, we show the possibility of detecting Einstein-Podolsky-Rosen steering and mode entanglement of non-Gaussian states from linear measurements only. Moreover, we show that such approach allows for a significantly higher noise robustness.