Chained Einstein-Podolsky-Rosen steering inequalities with improved visibility

TL;DR

This paper introduces chained Einstein-Podolsky-Rosen steering inequalities with enhanced visibility, enabling more efficient detection of steerability in Werner states with fewer measurement settings.

Contribution

The authors develop chained steering inequalities that outperform linear inequalities in detecting steerability, especially for finite measurement settings and generalized Werner states.

Findings

Lower threshold values for quantum violation in chained inequalities.

Improved visibility for almost all generalized Werner states.

Enhanced detection efficiency compared to linear inequalities.

Abstract

It is known that the linear n-setting steering inequalities introduced in Ref. [Nature Phys. 6, 845 (2010)] are very efficient inequalities in detecting steerability of the Werner states by using optimal measurement axes. Here, we construct chained steering inequalities that have improved visibility for the Werner states under a finite number of settings. Specifically, the threshold values of quantum violation of our inequalities for the n=4,6,10 settings are lower than those of the linear steering inequalities. Furthermore, for almost all generalized Werner states, the chained steering inequalities always have improved visibility in comparison with the linear steering inequalities.