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arXiv · 2401.12719

Device-independent quantum state discrimination

Xinyu Qiu·Lin Chen
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Abstract

Quantum state discrimination depicts the general progress of extracting classical information from quantum systems. We show that quantum state discrimination can be realized in a device-independent scenario using tools of self-testing results. That is, the states can be discriminated credibly with the untrusted experiment devices by the correspondence between quantum correlations and states. In detail, we show that two arbitrary states can be discriminated in a device-independent manner when they are not conjugate with each other, while other states can be discriminated measurement-device-independently. To fulfill the device-independent requirement, the measurements are restricted on Pauli observables. The influence of this restriction is acceptable based on the guessing probability analysis for minimum error discrimination.

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Xinyu Qiu, Lin Chen. 2024-01-23. Device-independent quantum state discrimination. https://doi.org/10.1016/j.physa.2024.129985

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