Direct Measure of Quantum Correlation

Abstract

The quantumness of the correlation known as quantum correlation is usually measured by quantum discord. So far various quantum discords can be roughly understood as indirect measure by some special discrepancy of two quantities. We present a direct measure of quantum correlation by revealing the difference between the structures of classically and quantum correlated states. Our measure explicitly includes the contributions of the inseparability and local non-orthogonality of the eigenvectors of a density. Besides its relatively easy computability, our measure can provide a unified understanding of quantum correlation of all the present versions.

References in corpus (11)

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Cited by in corpus (9)

• Quantum correlation measure in arbitrary bipartite systems
• Quantum correlation via quantum coherence
• Entangling Power in the Deterministic Quantum Computation with One Qubit
• The Dual Roles of Quantum Discord in a Non-demolition Probing Task
• The optimal approximation of qubit states with limited quantum states
• Quantum correlation cost of the weak measurement
• Analytically Computable Symmetric Quantum Correlations
• The best approximation of an objective state with a given set of quantum states
• The best approximation of a given qubit state with the limited pure-state set