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Distance measures to compare real and ideal quantum processes

Alexei Gilchrist·Nathan K. Langford·Michael A. Nielsen
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Abstract

With growing success in experimental implementations it is critical to identify a "gold standard" for quantum information processing, a single measure of distance that can be used to compare and contrast different experiments. We enumerate a set of criteria such a distance measure must satisfy to be both experimentally and theoretically meaningful. We then assess a wide range of possible measures against these criteria, before making a recommendation as to the best measures to use in characterizing quantum information processing.

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Alexei Gilchrist, Nathan K. Langford, Michael A. Nielsen. 2009-01-27. Distance measures to compare real and ideal quantum processes. https://doi.org/10.1103/physreva.71.062310

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