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arXiv · 2011.11340

How confused can an entanglement witness be to be still persuasive

Jan Roik·Karol Bartkiewicz·Antonín Černoch·Karel Lemr
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Abstract

Detection of entangled states is essential in both fundamental and applied quantum physics. However, this task proves to be challenging especially for general quantum states. One can execute full state tomography but this method is time demanding especially in complex systems. Other approaches use entanglement witnesses, these methods tend to be less demanding but lack reliability. Here, we demonstrate that ANN -- artificial neural networks provide a balance between both approaches. In this paper, we make a comparison of ANN performance against witness-based methods for random general 2-qubit quantum states without any prior information on the states. Furthermore, we apply our approach to real experimental data set.

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Jan Roik, Karol Bartkiewicz, Antonín Černoch, Karel Lemr. 2020-11-23. How confused can an entanglement witness be to be still persuasive. https://doi.org/10.1103/physrevapplied.15.054006

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