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arXiv · 1202.5058

Entanglement detection via mutually unbiased bases

Christoph Spengler·Marcus Huber·Stephen Brierley·Theodor Adaktylos·Beatrix C. Hiesmayr
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Abstract

We investigate correlations among complementary observables. In particular, we show how to take advantage of mutually unbiased bases (MUBs) for the efficient detection of entanglement in arbitrarily high-dimensional, multipartite and continuous variable quantum systems. The introduced entanglement criteria are relatively easy to implement experimentally since they require only a few local measurement settings. In addition, we establish a link between the separability problem and the maximum number of mutually unbiased bases -- opening a new avenue in this long-standing open problem.

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Christoph Spengler, Marcus Huber, Stephen Brierley, Theodor Adaktylos, Beatrix C. Hiesmayr. 2012-02-22. Entanglement detection via mutually unbiased bases. https://doi.org/10.1103/physreva.86.022311

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