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arXiv · 2101.04436

Retrieving High-Dimensional Quantum Steering From a Noisy Environment with N Measurement Settings

Abstract

One of the most often implied benefits of high-dimensional (HD) quantum systems is to lead to stronger forms of correlations, featuring increased robustness to noise. Here, we experimentally demonstrate the $n$-setting linear HD quantum steering criterion. We verify the large violation of the steering inequalities without full-state tomography. The lower bound of the violation is $2.24\pm0.01$ in 11 dimensions, exceeding the bound ($V<2$) of 2-setting criteria. Hence, a higher strength of steering has been revealed. Moreover, we demonstrate the method for enhancing the noise robustness without increasing dimension, alternatively, by increasing measurement settings. Using the entanglement in 11 dimensions, we experimentally retrieve steering nonlocality with $63.4\pm1.4\%$ isotropic noise fraction, surpassing the $50\%$ limitation of 2-setting criteria. Our work offers the potential for practical one-sided device-independent quantum information processing that tolerates the noisy environment, lossy detection, and transcends the present transmission distance limitation.

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Rui Qu, Yunlong Wang, Min An, Feiran Wang, Quan Quan, Hongrong Li, Hong Gao, Fuli Li, Pei Zhang. 2021-01-12. Retrieving High-Dimensional Quantum Steering From a Noisy Environment with N Measurement Settings. https://doi.org/10.1103/physrevlett.128.240402

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