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arXiv · 1504.08225

Detecting Entanglement of Unknown Quantum States with Random Measurements

Jochen Szangolies·Hermann Kampermann·Dagmar Bruß
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Abstract

In quantum information theory, the reliable and effective detection of entanglement is of paramount importance. However, given an unknown state, assessing its entanglement is a challenging task. To attack this problem, we investigate the use of random local measurements, from which entanglement witnesses are then constructed via semidefinite programming methods. We propose a scheme of successively increasing the number of measurements until the presence of entanglement can be unambiguously concluded, and investigate its performance in various examples.

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Jochen Szangolies, Hermann Kampermann, Dagmar Bruß. 2015-04-30. Detecting Entanglement of Unknown Quantum States with Random Measurements. https://doi.org/10.1088/1367-2630/17/11/113051

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