Self-testing entangled measurements in quantum networks

TL;DR

This paper develops methods for self-testing entangled quantum measurements in networks, particularly certifying Bell-state measurements with robustness to noise, advancing quantum network verification techniques.

Contribution

It introduces a natural assumption-based framework for self-testing entangled measurements, including a robust method for Bell-state measurement certification.

Findings

Robust self-test for Bell-state measurement with up to 5% noise tolerance

Framework based on independence assumption of sources in quantum networks

Discussion of generalizations to other entangled measurements

Abstract

Self-testing refers to the possibility of characterizing an unknown quantum device based only on the observed statistics. Here we develop methods for self-testing entangled quantum measurements, a key element for quantum networks. Our approach is based on the natural assumption that separated physical sources in a network should be considered independent. This provides a natural formulation of the problem of certifying entangled measurements. Considering the setup of entanglement swapping, we derive a robust self-test for the Bell-state measurement, tolerating noise levels up to 5%. We also discuss generalizations to other entangled measurements.