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arXiv · 1205.3517

On the spectral dependence of separable and classical correlations in small quantum systems

Gary McConnell·David Jennings
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Abstract

We study the correlation structure of separable and classical states in 2x2- and 2x3-dimensional quantum systems with fixed spectra. Even for such simple systems the maximal correlation - as measured by mutual information - over the set of unitarily accessible separable states is highly non-trivial to compute; however for the 2x2 case a particular class of spectra admits full analysis and allows us to contrast classical states with more general separable states. We analyse a particular entropic partial order on the set of spectra and prove for the qubit-qutrit case that this partial order alone picks out a unique classical maximum state for mutual information. Moreover the 2x3 case is the largest system with such a property.

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Gary McConnell, David Jennings. 2012-09-11. On the spectral dependence of separable and classical correlations in small quantum systems. https://arxiv.org/abs/1205.3517

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