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Updated: Jan 1, 2026

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Quantum Beat between Sunlight and Single Photons
Zhao-Chen Duan1,2, Yu-Hao Deng1,2, Ying Yu3
1Shanghai Branch, Department of Modern Physics and National Laboratory for Physical Sciences at Microscale , University of Science and Technology of China , Shanghai 201315 , China.
Abstract:
We demonstrate fourth-order quantum beat between sunlight and single photons from a quantum dot. With a fast time-resolved detection system, we observed high-visibility quantum beat between the independent photons of different frequencies from the two astronomically separated light sources. The temporal dynamics of the beat oscillation indicate the coherent behavior of the interfering photons, and the raw visibility of two-photon interference shows violation of the classical limit with a frequency mismatch of three-times the line width.
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