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arXiv · 1310.8465

Systematic errors in current quantum state tomography tools

Christian Schwemmer·Lukas Knips·Daniel Richart·Tobias Moroder·Matthias Kleinmann·Otfried Gühne·Harald Weinfurter
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Abstract

Common tools for obtaining physical density matrices in experimental quantum state tomography are shown here to cause systematic errors. For example, using maximum likelihood or least squares optimization for state reconstruction, we observe a systematic underestimation of the fidelity and an overestimation of entanglement. A solution for this problem can be achieved by a linear evaluation of the data yielding reliable and computational simple bounds including error bars.

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Christian Schwemmer, Lukas Knips, Daniel Richart, Tobias Moroder, Matthias Kleinmann, Otfried Gühne, Harald Weinfurter. 2013-10-31. Systematic errors in current quantum state tomography tools. https://doi.org/10.1103/physrevlett.114.080403

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