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arXiv · 0709.0824

On Random Unitary Channels

Koenraad M. R. Audenaert·Stefan Scheel
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Abstract

In this article we provide necessary and sufficient conditions for a completely positive trace-preserving (CPT) map to be decomposable into a convex combination of unitary maps. Additionally, we set out to define a proper distance measure between a given CPT map and the set of random unitary maps, and methods for calculating it. In this way one could determine whether non-classical error mechanisms such as spontaneous decay or photon loss dominate over classical uncertainties, for example in a phase parameter. The present paper is a step towards achieving this goal.

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Koenraad M. R. Audenaert, Stefan Scheel. 2007-09-06. On Random Unitary Channels. https://doi.org/10.1088/1367-2630%2F10%2F2%2F023011

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