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arXiv · 1808.09988

Confidence Polytopes in Quantum State Tomography

Jinzhao Wang·Volkher B. Scholz·Renato Renner
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Abstract

Quantum State Tomography is the task of inferring the state of a quantum system from measurement data. A reliable tomography scheme should not only report an estimate for that state, but also well-justified error bars. These may be specified in terms of confidence regions, i.e., subsets of the state space which contain the system's state with high probability. Here, building upon a quantum generalisation of Clopper-Pearson confidence intervals--a notion known from classical statistics--we present a simple and reliable scheme for generating confidence regions. These have the shape of a polytope and can be computed efficiently. We provide several examples to demonstrate the practical usability of the scheme in experiments.

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Jinzhao Wang, Volkher B. Scholz, Renato Renner. 2018-08-29. Confidence Polytopes in Quantum State Tomography. https://doi.org/10.1103/physrevlett.122.190401

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