Practical measurement-device-independent entanglement quantification

TL;DR

This paper introduces a practical method to quantify entanglement using measurement-device-independent witnesses, enabling reliable entanglement estimation without perfect measurement devices, which is crucial for validating quantum systems.

Contribution

It demonstrates that measurement-device-independent entanglement witnesses can be used to quantify entanglement, providing a practical approach based solely on experimental data.

Findings

MDIEWs can quantify entanglement according to standard measures.

The method works with experimental data without requiring perfect measurements.

It enhances the robustness of entanglement validation in quantum systems.

Abstract

The robust estimation of entanglement is key to the validation of implementations of quantum systems. On the one hand, the evaluation of standard entanglement measures, either using quantum tomography or using quantitative entanglement witnesses requires perfect implementation of measurements. On the other hand, measurement-device-independent entanglement witnesses (MDIEWs) can certify entanglement of all entangled states using untrusted measurement devices. We show that MDIEWs can be used as well to quantify entanglement according to standard entanglement measures, and present a practical method to derive such witnesses using experimental data only.