Single-measurement Bell analysis

TL;DR

This paper investigates Bell inequalities in single quantum system measurements, demonstrating that joint noisy measurements can violate Bell bounds, highlighting the necessity of nonclassical measurement schemes to reveal quantum nonlocality.

Contribution

It introduces a method to analyze Bell criteria for single realizations using joint noisy measurements, showing violations of Bell bounds in such scenarios.

Findings

Every outcome violates Bell bounds for local hidden variable models.

Nonclassical measurement schemes are necessary to reveal nonclassical effects.

Joint noisy measurements can demonstrate Bell inequality violations in single measurements.

Abstract

We examine the satisfaction of Bell criteria for single realizations of quantum systems. This is possible via the joint noisy measurement of all observables involved in the Bell test.We readily find that every outcome violates Bell bounds for local hidden variables models. This agrees with the idea that to reveal nonclassical effects a necessary condition is that the measuring scheme itself must be nonclassical.