Nonlocality, steering and quantum state tomography in a single experiment

TL;DR

This paper demonstrates a unified experimental approach using quantum state tomography measurements to certify entanglement, steering, and nonlocality in a single photonic setup, simplifying quantum correlation detection.

Contribution

It introduces a noise-robust correlation witness applicable to tomography experiments, enabling simultaneous testing of entanglement, steering, and nonlocality.

Findings

Successful state tomography of entangled qutrits

Demonstration of EPR steering and Bell inequality violation in one experiment

Validation of quantum correlations with varying trust assumptions

Abstract

We investigate whether paradigmatic measurements for quantum state tomography, namely mutually unbiased bases and symmetric informationally complete measurements, can be employed to certify quantum correlations. For this purpose, we identify a simple and noise-robust correlation witness for entanglement detection, steering and nonlocality that can be evaluated based on the outcome statistics obtained in the tomography experiment. This allows us to perform state tomography on entangled qutrits, a test of Einstein-Podolsky-Rosen steering and a Bell inequality test, all within a single experiment. We also investigate the trade-off between quantum correlations and subsets of tomographically complete measurements as well as the quantification of entanglement in the different scenarios. Finally, we perform a photonics experiment in which we demonstrate quantum correlations under these flexible assumptions, namely with both parties trusted, one party untrusted and both parties untrusted.