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arXiv · 1511.04886

All the self-testings of the singlet for two binary measurements

Yukun Wang·Xingyao Wu·Valerio Scarani
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Abstract

Self-testing refers to the possibility of characterizing uniquely (up to local isometries) the state and measurements contained in quantum devices, based only on the observed input-output statistics. Already in the basic case of the two-qubit singlet, self-testing is not unique: the two known criteria (the maximal violation of the CHSH inequality and the Mayers-Yao correlations) are not equivalent. It is unknown how many criteria there are. In this paper, we find the whole set of criteria for the ideal self-testing of singlet with two measurements and two outcomes on each side: it coincides with all the extremal points of the quantum set that can be obtained by measuring the singlet.

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Yukun Wang, Xingyao Wu, Valerio Scarani. 2015-11-16. All the self-testings of the singlet for two binary measurements. https://doi.org/10.1088/1367-2630%2F18%2F2%2F025021

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