arXiv:1108.2233

On exposed positive maps: Robertson and Breuer-Hall maps

Dariusz Chruściński

Published Aug 10, 2011• 2 citations

Abstract

It is well known that so called Breuer-Hall positive maps used in entanglement theory are optimal. We show that these maps possess much more subtle property --- they are exposed. As a byproduct it proves that a Robertson map in the algebra of 4 x 4 complex matrices is not only extreme, which was already shown by Robertson, but also exposed.

DOI: 10.48550/arxiv.1108.2233

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