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

• URL: http://arxiv.org/abs/2204.07765v1
• Date: Sat, 16 Apr 2022 09:42:57 GMT
• Title: Experimental violation of the Leggett-Garg inequality with a single-spin system
• Authors: Maimaitiyiming Tusun, Wei Cheng, Zihua Chai, Yang Wu, Ya Wang, Xing Rong, Jiangfeng Du
• Abstract summary: We present an experimental violation of the Leggett-Garg inequality in a three-level system using nitrogen-vacancy center in diamond. The experimental maximum value of Leggett-Garg function is $K_3exp=1.625pm0.022$ which exceeds the L"uders bound with a $5sigma$ level of confidence.
• Score: 19.252331846706017
• License: http://creativecommons.org/licenses/by/4.0/
• 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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