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arXiv · 1810.05588

Entanglement detection by violations of noisy uncertainty relations: A proof of principle

Yuan-Yuan Zhao·Guo-Yong Xiang·Xiao-Min Hu·Bi-Heng Liu·Chuan-Feng Li·Guang-Can Guo·René Schwonnek·Ramona Wolf
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Abstract

It is well-known that the violation of a local uncertainty relation can be used as an indicator for the presence of entanglement. Unfortunately, the practical use of these non-linear witnesses has been limited to few special cases in the past. However, new methods for computing uncertainty bounds became available. Here we report on an experimental implementation of uncertainty-based entanglement witnesses, benchmarked in a regime dominated by strong local noise. We combine the new computational method with a local noise tomography in order to design noise-adapted entanglement witnesses. This proof-of-principle experiment shows that quantum noise can be successfully handled by a fully quantum model in order to enhance entanglement detection efficiencies.

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Yuan-Yuan Zhao, Guo-Yong Xiang, Xiao-Min Hu, Bi-Heng Liu, Chuan-Feng Li, Guang-Can Guo, René Schwonnek, Ramona Wolf. 2018-10-12. Entanglement detection by violations of noisy uncertainty relations: A proof of principle. https://doi.org/10.1103/physrevlett.122.220401

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