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arXiv · 1901.00999

Measurement-device-independent quantification of irreducible high-dimensional entanglement

Yu Guo·Bai-Chu Yu·Xiao-Min Hu·Bi-Heng Liu·Yu-Chun Wu·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo
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Abstract

The certification of entanglement dimensionality is of great importance in characterizing quantum systems. Recently, it is pointed out that quantum correlation of high-dimensional states can be simulated with a sequence of lower-dimensional states. Such problem may render existing characterization protocols unreliable---the observed entanglement may not be a truly high-dimensional one. Here, we introduce the notion of irreducible entanglement to capture its dimensionality that is indecomposable in terms of a sequence of lower-dimensional entangled systems. We prove this new feature can be detected in a measurement-device-independent manner with an entanglement witness protocol. To demonstrate the practicability of this technique, we experimentally apply it on a 3-dimensional bipartite state and the result certifies the existence of irreducible (at least) 3-dimensional entanglement.

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Yu Guo, Bai-Chu Yu, Xiao-Min Hu, Bi-Heng Liu, Yu-Chun Wu, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo. 2019-01-04. Measurement-device-independent quantification of irreducible high-dimensional entanglement. https://doi.org/10.1038/s41534-020-0282-4

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