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arXiv · 1209.2176

Experimental detection of quantum coherent evolution through the violation of Leggett-Garg-type inequalities

Zong-Quan Zhou·Susana F. Huelga·Chuan-Feng Li·Guang-Can Guo
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Abstract

We discuss the use of inequalities of the Leggett-Garg type (LGtI) to witness quantum coherence and present the first experimental violation of this type of inequalities using a light-matter interfaced system. By separately benchmarking the Markovian character of the evolution and the translational invariance of the conditional probabilities, the observed violation of a LGtI is attributed to the quantum coherent character of the process. These results provide a general method to benchmark `quantumness' when the absence of memory effects can be independently certified and confirm the persistence of quantum coherent features within systems of increasing complexity.

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Zong-Quan Zhou, Susana F. Huelga, Chuan-Feng Li, Guang-Can Guo. 2012-09-10. Experimental detection of quantum coherent evolution through the violation of Leggett-Garg-type inequalities. https://doi.org/10.1103/physrevlett.115.113002

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