Experimental violation of Leggett-Garg inequality in a three-level trapped-ion system

• URL: http://arxiv.org/abs/2209.07254v1
• Date: Thu, 15 Sep 2022 12:42:30 GMT
• Title: Experimental violation of Leggett-Garg inequality in a three-level trapped-ion system
• Authors: Tianxiang Zhan, Chunwang Wu, Manchao Zhang, Qingqing Qin, Xueying Yang, Han Hu, Wenbo Su, Jie Zhang, Ting Chen, Yi Xie, Wei Wu, Pingxing Chen
• Abstract summary: We experimentally test the Leggett-Garg inequality (LGI) in a three-level trapped-ion system under the model of a large spin precessing in a magnetic field. The maximum observed value of Leggett-Garg correlator under the Von Neumann state update rule is $K_3 = 1.739 pm 0.014$.
• Score: 17.179848278254454
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Leggett-Garg inequality (LGI) studies the temporal correlation in the evolution of physical systems. Classical systems obey the LGI but quantum systems may violate it. The extent of the violation depends on the dimension of the quantum system and the state update rule. In this work, we experimentally test the LGI in a three-level trapped-ion system under the model of a large spin precessing in a magnetic field. The Von Neumann and L\"uders state update rules are employed in our system for direct comparative analysis. The maximum observed value of Leggett-Garg correlator under the Von Neumann state update rule is $K_3 = 1.739 \pm 0.014$, which demonstrates a violation of the L\"uders bound by 17 standard deviations and is by far the most significant violation in natural three-level systems.

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