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arXiv · 2206.10828

Experimental Test of Contextuality based on State Discrimination with a Single Qubit

Qiuxin Zhang·Chenhao Zhu·Yuxin Wang·Liangyu Ding·Tingting Shi·Xiang Zhang·Shuaining Zhang·Wei Zhang
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Abstract

Exploring quantum phenomena beyond predictions of any classical model has fundamental importance to understand the boundary of classical and quantum descriptions of nature. As a typical property that a quantum system behaves distinctively from a classical counterpart, contextuality has been studied extensively and verified experimentally in systems composed of at least three levels (qutrit). Here we extend the scope of experimental test of contextuality to a minimal quantum system of only two states (qubit) by implementing the minimum error state discrimination on a single $^{171}$Yb$^+$ ion. We observe a substantial violation of a no-go inequality derived by assuming non-contextuality, and firmly conclude that the measured results of state discrimination cannot be reconciled with any non-contextual description. We also quantify the contextual advantage of state discrimination and the tolerance against quantum noises.

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Qiuxin Zhang, Chenhao Zhu, Yuxin Wang, Liangyu Ding, Tingting Shi, Xiang Zhang, Shuaining Zhang, Wei Zhang. 2022-06-22. Experimental Test of Contextuality based on State Discrimination with a Single Qubit. https://doi.org/10.1088/0256-307x%2F39%2F8%2F080301

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