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arXiv:quant-ph/0408063 · Physical Review A

Distance measures to compare real and ideal quantum processes

Alexei Gilchrist, Nathan K. Langford, Michael A. Nielsen

Published Jun 13, 2005• 654 citations
arXivHTMLPDF

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 that 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.

DOI
10.1103/physreva.71.062310

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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 that 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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