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arXiv · 1310.4492

Robust, self-consistent, closed-form tomography of quantum logic gates on a trapped ion qubit

Robin Blume-Kohout·John King Gamble·Erik Nielsen·Jonathan Mizrahi·Jonathan D. Sterk·Peter Maunz
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Abstract

We introduce and demonstrate experimentally: (1) a framework called "gate set tomography" (GST) for self-consistently characterizing an entire set of quantum logic gates on a black-box quantum device; (2) an explicit closed-form protocol for linear-inversion gate set tomography (LGST), whose reliability is independent of pathologies such as local maxima of the likelihood; and (3) a simple protocol for objectively scoring the accuracy of a tomographic estimate without reference to target gates, based on how well it predicts a set of testing experiments. We use gate set tomography to characterize a set of Clifford-generating gates on a single trapped-ion qubit, and compare the performance of (i) standard process tomography; (ii) linear gate set tomography; and (iii) maximum likelihood gate set tomography.

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Robin Blume-Kohout, John King Gamble, Erik Nielsen, Jonathan Mizrahi, Jonathan D. Sterk, Peter Maunz. 2013-10-16. Robust, self-consistent, closed-form tomography of quantum logic gates on a trapped ion qubit. https://arxiv.org/abs/1310.4492

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