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arXiv · 1105.3419

Characterizing quantumness via entanglement creation

Sevag Gharibian·Marco Piani·Gerardo Adesso·John Calsamiglia·Pawel Horodecki
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Abstract

In [M. Piani et al., arXiv:1103.4032 (2011)] an activation protocol was introduced which maps the general non-classical (multipartite) correlations between given systems into bipartite entanglement between the systems and local ancillae by means of a potentially highly entangling interaction. Here, we study how this activation protocol can be used to entangle the starting systems themselves via entanglement swapping through a measurement on the ancillae. Furthermore, we bound the relative entropy of quantumness (a naturally arising measure of non-classicality in the scheme of Piani et al. above) for a special class of separable states, the so-called classical-quantum states. In particular, we fully characterize the classical-quantum two-qubit states that are maximally non-classical.

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Sevag Gharibian, Marco Piani, Gerardo Adesso, John Calsamiglia, Pawel Horodecki. 2011-05-17. Characterizing quantumness via entanglement creation. https://doi.org/10.1142/s0219749911008258

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