Dominance of quantum over classical correlations: entropic and geometric approach

TL;DR

This paper investigates the dominance of quantum correlations over classical correlations in two-qubit Bell diagonal states using entropic and geometric measures, revealing ambiguities between the two approaches.

Contribution

It provides a numerical analysis of quantum versus classical correlation dominance in Bell diagonal states and compares entropic and geometric quantification methods.

Findings

Quantum correlations can dominate over classical correlations in certain states.

Entropic and geometric approaches sometimes yield ambiguous results.

Numerical estimates of correlation dominance are provided for Bell diagonal states.

Abstract

Recently, it has been shown that there exist quantum states for which quantum correlations dominate over classical correlations. Inspired by this observation, we investigate the problem of quantum correlations dominance for two-qubit Bell diagonal states in the Ollivier--Zurek paradigm, using both entropic and geometric approach to quantification of classical and quantum correlations. In particular, we estimate numerically the amount of two-qubit Bell diagonal states for which quantum correlations dominate over classical correlations, and vice versa. Moreover, we show that in general these two approaches to quantification of correlations provide ambiguous results.