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arXiv · 2110.15176

Self-testing of any pure entangled state with minimal number of measurements and optimal randomness certification in one-sided device-independent scenario

Shubhayan Sarkar·Jakub J. Borkała·Chellasamy Jebarathinam·Owidiusz Makuta·Debashis Saha·Remigiusz Augusiak
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Abstract

Certification of quantum systems and their properties has become a field of intensive studies. Here, taking advantage of the one-sided device-independent scenario (known also as quantum steering scenario), we propose a self-testing scheme for all bipartite entangled states using a single family of steering inequalities with the minimal number of two measurements per party. Building on this scheme we then show how to certify all rank-one extremal measurements, including non-projective $d^2$-outcome measurements, which in turn can be used for certification of the maximal amount of randomness from every entangled bipartite state of local dimension $d$, that is, $2\log_2d$ bits. Finally, in a particular case of $d=3$, we extend our self-testing results to the fully device-independent setting.

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Shubhayan Sarkar, Jakub J. Borkała, Chellasamy Jebarathinam, Owidiusz Makuta, Debashis Saha, Remigiusz Augusiak. 2021-10-28. Self-testing of any pure entangled state with minimal number of measurements and optimal randomness certification in one-sided device-independent scenario. https://doi.org/10.1103/physrevapplied.19.034038

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