Quantum Beat between Sunlight and Single Photons
Z.-C. Duan, Yu-Hao Deng, Ying Yu, Si Chen, Jian Qin, Hui Wang, Xing Ding, Li-Chao Peng, Christian Schneider, Da‐Wei Wang, Sven Höfling, Jonathan P. Dowling, Chao‐Yang Lu, Jian-Wei Pan · Nano Letters · 2019
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.