Violation of Bells inequality using continuous variable measurements

TL;DR

This paper demonstrates a violation of Bell's inequality using continuous variable quadrature measurements, showing potential for device-independent quantum protocols with continuous variable states.

Contribution

It is the first to show Bell inequality violation with continuous variable measurements using a four-mode entangled state and homodyne detection.

Findings

Bell value of 2.31 ± 0.02 achieved

Violated Bell inequality with continuous variables

Potential for device-independent quantum protocols

Abstract

A Bell inequality is a fundamental test to rule out local hidden variable model descriptions of correlations between two physically separated systems. There have been a number of experiments in which a Bell inequality has been violated using discrete-variable systems. We demonstrate a violation of Bells inequality using continuous variable quadrature measurements. By creating a four-mode entangled state with homodyne detection, we recorded a clear violation with a Bell value of $B = 2.31 \pm 0.02$. This opens new possibilities for using continuous variable states for device independent quantum protocols.