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arXiv · 2011.02217

Optimized detection of high-dimensional entanglement

Xiao-Min Hu·Wen-Bo Xing·Yu Guo·Mirjam Weilenmann·Edgar A. Aguilar·Xiaoqin Gao·Bi-Heng Liu·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Zizhu Wang·Miguel Navascués
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Abstract

Entanglement detection is one of the most conventional tasks in quantum information processing. While most experimental demonstrations of high-dimensional entanglement rely on fidelity-based witnesses, these are powerless to detect entanglement within a large class of entangled quantum states, the so-called unfaithful states. In this paper, we introduce a highly flexible automated method to construct optimal tests for entanglement detection given a bipartite target state of arbitrary dimension, faithful or unfaithful, and a set of local measurement operators. By restricting the number or complexity of the considered measurement settings, our method outputs the most convenient protocol which can be implemented using a wide range of experimental techniques such as photons, superconducting qudits, cold atoms or trapped ions. With an experimental quantum optics setup that can prepare and measure arbitrary high-dimensional mixed states, we implement some $3$-setting protocols generated by our method. These protocols allow us to experimentally certify 2- and 3-unfaithful entanglement in 4-dimensional photonic states, some of which contain well above 50% of noise.

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Xiao-Min Hu, Wen-Bo Xing, Yu Guo, Mirjam Weilenmann, Edgar A. Aguilar, Xiaoqin Gao, Bi-Heng Liu, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Zizhu Wang, Miguel Navascués. 2021-10-29. Optimized detection of high-dimensional entanglement. https://doi.org/10.1103/physrevlett.127.220501

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