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arXiv · 1803.03213

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

Suchetana Goswami·Bihalan Bhattacharya·Debarshi Das·Souradeep Sasmal·C. Jebaratnam·A. S. Majumdar
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Abstract

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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Suchetana Goswami, Bihalan Bhattacharya, Debarshi Das, Souradeep Sasmal, C. Jebaratnam, A. S. Majumdar. 2018-03-08. One-sided Device-independent Self-testing of any Pure Two-qubit Entangled State. https://doi.org/10.1103/physreva.98.022311

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