# Testing contextuality on quantum ensembles with one clean qubit

## TL;DR

This paper introduces a protocol to test quantum contextuality on ensembles of quantum systems, demonstrated experimentally with NMR techniques on molecular nuclear spins, showing violation of non-contextual hidden-variable inequalities.

## Contribution

It provides a new experimental method to evaluate quantum contextuality on large ensembles using NMR, bridging theory and practical quantum information processing.

## Key findings

- Demonstrated violation of non-contextual inequalities
- Developed a protocol for expectation value measurement on ensembles
- Used NMR techniques on solid-state nuclear spins

## Abstract

We present a protocol to evaluate the expectation value of the correlations of measurement outcomes for ensembles of quantum systems, and use it to experimentally demonstrate--under an assumption of fair sampling--the violation of an inequality that is satisfied by any non-contextual hidden-variables (NCHV) theory. The experiment is performed on an ensemble of molecular nuclear spins in the solid state, using established Nuclear Magnetic Resonance (NMR) techniques for quantum information processing (QIP).