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One-sided Device-independent Self-testing of any Pure Two-qubit Entangled State

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 نشر من قبل Suchetana Goswami
 تاريخ النشر 2018
  مجال البحث فيزياء
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We consider the problem of $1$-sided device-independent self-testing of any pure entangled two-qubit state based on steering inequalities which certify the presence of quantum steering. In particular, we note that in the $2-2-2$ steering scenario (involving $2$ parties, $2$ measurement settings per party, $2$ outcomes per measurement setting), the maximal violation of a fine-grained steering inequality can be used to witness certain extremal steerable correlations, which certify all pure two-qubit entangled states. We demonstrate that the violation of analogous CHSH inequality of steering or nonvanishing value of a quantity constructed using a correlation function called mutual predictability together with the maximal violation of fine-grained steering inequality can be used to self-test any pure entangled two-qubit state in a $1$-sided device-independent way.



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