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arXiv · 1305.0990

Device-independent randomness amplification with a single device

Martin Plesch·Matej Pivoluska
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Abstract

Expansion and amplification of weak randomness with untrusted quantum devices has recently become a very fruitful topic of research. Here we contribute with a procedure for amplifying a single weak random source using tri-partite GHZ-type entangled states. If the quality of the source reaches a fixed threshold $R=\frac{1}{4}\log_{2}(10)$, perfect random bits can be produced. This technique can be used to extract randomness from sources that can't be extracted neither classically, nor by existing procedures developed for Santha-Vazirani sources. Our protocol works with a single fault-free device decomposable into three non-communicating parts, that is repeatedly reused throughout the amplification process.

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Martin Plesch, Matej Pivoluska. 2014-08-06. Device-independent randomness amplification with a single device. https://doi.org/10.1016/j.physleta.2014.08.007

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