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arXiv · 1801.08520

Self-testing quantum states and measurements in the prepare-and-measure scenario

Armin Tavakoli·Jędrzej Kaniewski·Tamás Vértesi·Denis Rosset·Nicolas Brunner
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Abstract

The goal of self-testing is to characterize an a priori unknown quantum system based solely on measurement statistics, i.e. using an uncharacterized measurement device. Here we develop self-testing methods for quantum prepare-and-measure experiments, thus not necessarily relying on entanglement and/or violation of a Bell inequality. We present noise-robust techniques for self-testing sets of quantum states and measurements, assuming an upper bound on the Hilbert space dimension. We discuss in detail the case of a $2 \rightarrow 1$ random access code with qubits, for which we provide analytically optimal self-tests. The simplicity and noise robustness of our methods should make them directly applicable to experiments.

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Armin Tavakoli, Jędrzej Kaniewski, Tamás Vértesi, Denis Rosset, Nicolas Brunner. 2018-01-25. Self-testing quantum states and measurements in the prepare-and-measure scenario. https://doi.org/10.1103/physreva.98.062307

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