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arXiv · 1707.07723

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

Marco Cianciaruso·Irénée Frérot·Tommaso Tufarelli·Gerardo Adesso
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Abstract

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.

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Marco Cianciaruso, Irénée Frérot, Tommaso Tufarelli, Gerardo Adesso. 2019-01-26. Characterising two-sided quantum correlations beyond entanglement via metric-adjusted f-correlations. https://doi.org/10.1007/978-3-319-97798-0_18

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