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arXiv · 1803.05199

Maximal randomness expansion from steering inequality violations using qudits

Paul Skrzypczyk·Daniel Cavalcanti
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Abstract

We consider the generation of randomness based upon the observed violation of an Einstein-Podolsky-Rosen (EPR) steering inequality, known as one-sided device-independent randomness expansion. We show that in the simplest scenario -- involving only two parties applying two measurements with $d$ outcomes each -- that there exist EPR steering inequalities whose maximal violation certifies the maximal amount of randomness, equal to log(d) bits. We further show that all pure partially entangled full-Schmidt-rank states in all dimensions can achieve maximal violation of these inequalities, and thus lead to maximal randomness expansion in the one-sided device-independent setting. More generally, the amount of randomness that can be certified is given by a semidefinite program, which we use to study the behaviour for non-maximal violations of the inequalities.

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Paul Skrzypczyk, Daniel Cavalcanti. 2018-03-14. Maximal randomness expansion from steering inequality violations using qudits. https://doi.org/10.1103/physrevlett.120.260401

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