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Updated: Apr 3, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Experimental detection of quantum coherent evolution through the violation of Leggett-Garg-type inequalities
Zong-Quan Zhou1,2, Susana F Huelga3, Chuan-Feng Li1,2
1Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China.
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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