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arXiv · 1610.00041

Determining quantum correlations in bipartite systems - from qubit to qutrit and beyond

Andrzej Frydryszak·Lech Jakóbczyk·Piotr Ługiewicz
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Abstract

We advocate the step change in properties of discrete $d$-level quantum systems, between $d=2$ and $d\geq 3$. Qubit systems, or multipartite systems containing qubit subsystem, are exceptional in their relative simplicity. One faces a step in complexity in valuating measures of quantum correlations for qutrits and then other higher dimensional qudits. There is a growing number of arguments leading to such conclusion: recently found no-go theorem for generalization of the Peres-Horodecki's PPT criterion \cite{sko}, change in geometry of state spaces of qubit and higher degree qudits (the so called 'generalized Bloch ball' is not a ball anymore), restricted possibilities for diagonalization of correlation matrices for bipartite systems, more difficult way for handling the set of relevant families of orthogonal projectors.

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Andrzej Frydryszak, Lech Jakóbczyk, Piotr Ługiewicz. 2016-09-30. Determining quantum correlations in bipartite systems - from qubit to qutrit and beyond. https://doi.org/10.1088/1742-6596%2F804%2F1%2F012016

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