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arXiv · 2112.01139

Locking and unlocking of quantum nonlocality without entanglement in local discrimination of quantum states

Donghoon Ha·Jeong San Kim
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Abstract

The phenomenon of nonlocality without entanglement(NLWE) arises in discriminating multi-party quantum separable states. Recently, it has been found that the post-measurement information about the prepared subensemble can lock or unlock NLWE in minimum-error discrimination of non-orthogonal separable states. Thus, it is natural to ask whether the availability of the post-measurement information can influence on the occurrence of NLWE even in other state-discrimination strategies. Here, we show that the post-measurement information can be used to lock as well as unlock the occurrence of NLWE in terms of optimal unambiguous discrimination. Our results can provide a useful application for hiding or sharing information based on non-orthogonal separable states.

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Donghoon Ha, Jeong San Kim. 2021-12-02. Locking and unlocking of quantum nonlocality without entanglement in local discrimination of quantum states. https://doi.org/10.1038/s41598-022-07930-w

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