Characterising two-sided quantum correlations beyond entanglement via metric-adjusted f-correlations

• Published in: arXiv.org
• Main Authors: Cianciaruso, Marco, Frérot, Irénée, Tufarelli, Tommaso, Adesso, Gerardo
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 26.01.2019
• Subjects: Correlation; Mathematics - Mathematical Physics; Physics - Data Analysis, Statistics and Probability; Physics - High Energy Physics - Theory; Physics - Mathematical Physics; Physics - Quantum Physics; Physics - Statistical Mechanics; Quantum entanglement; Quantum theory; Qubits (quantum computing); Systems analysis
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1707.07723

We introduce an infinite family of quantifiers of quantum correlations beyond entanglement which vanish on both classical-quantum and quantum-classical states and are in one-to-one correspondence with the metric-adjusted skew informations. The `quantum \(f-\)correlations' are defined as the maximum metric-adjusted \(f-\)correlations between pairs of local observables with the same fixed equispaced spectrum. We show that these quantifiers are entanglement monotones when restricted to pure states of qubit-qudit systems. We also evaluate the quantum \(f-\)correlations in closed form for two-qubit systems and discuss their behaviour under local commutativity preserving channels. We finally provide a physical interpretation for the quantifier corresponding to the average of the Wigner-Yanase-Dyson skew informations.