Physica Scripta

Entropy-based geometric measures of correlations for bell diagonal states via measurement

Yutong Liu, Hua Nan, Lin Zhang, Yan Jin, Yicheng Hong

Published Oct 21, 2024• 1 citation

Abstract

Abstract The classification and quantification of quantum correlations are the important issues in quantum information theory. Quantum relative entropy and Rényi relative entropy are both non-negative, and can therefore be regarded as generalized distances between quantum states. We first introduced the method proposed by Brodutch and Modi for constructing measurements of classical and quantum correlations. Subsequently, we use this method to construct measurement-induced geometric classical and quantum correlations based on quantum relative entropy and Rényi− 1 2 relative entropy. For two-qubit Bell diagonal states, the analytic expressions for these geometric classical correlations and quantum correlations are obtained.

DOI: 10.1088/1402-4896/ad897d

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