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arXiv · 2204.07765

Experimental violation of the Leggett-Garg inequality with a single-spin system

Maimaitiyiming Tusun·Wei Cheng·Zihua Chai·Yang Wu·Ya Wang·Xing Rong·Jiangfeng Du
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Abstract

Investigation the boundary between quantum mechanical description and classical realistic view is of fundamental importance. The Leggett-Garg inequality provides a criterion to distinguish between quantum systems and classical systems, and can be used to prove the macroscopic superposition state. A larger upper bound of the LG function can be obtained in a multi-level system. Here, we present an experimental violation of the Leggett-Garg inequality in a three-level system using nitrogen-vacancy center in diamond by ideal negative result measurement. The experimental maximum value of Leggett-Garg function is $K_{3}^{exp}=1.625\pm0.022$ which exceeds the L\"uders bound with a $5\sigma$ level of confidence.

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Maimaitiyiming Tusun, Wei Cheng, Zihua Chai, Yang Wu, Ya Wang, Xing Rong, Jiangfeng Du. 2022-04-16. Experimental violation of the Leggett-Garg inequality with a single-spin system. https://doi.org/10.1103/physreva.105.042613

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