Non-Classical Correlated Photon Pairs Generation via Cascade Transition of 5S1/2–5P3/2–5D5/2 in a Hot 85Rb Atomic Vapor
ZHANG Wei1,2, DING Dong-Sheng1,2, PAN Jian-Song1,2, SHI Bao-Sen1,2**
1Key Laboratory of Quantum Information, Chinese Academy of Sciences, University of Science and Technology of China, Hefei 230026 2Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026
Abstract:We experimentally prepare the non-classical correlated photon pairs at the wavelengths of 780 and 776 nm via the cascade transition of 5S1/2–5P3/2–5D5/2 in a hot 85Rb atomic ensemble. By measuring the function of cross-correlation and auto-correlation of photons, a violation of Cauchy–Schwarz inequality by a factor of 283 is obtained, which clearly indicates a strong non-classical correlation between the generated photons. We also find that noise photons scattered from pump lasers have a strong effect on the Cauchy–Schwarz inequality factor by changing the intensity of the pump laser, the experimental results are consistent with the theoretical predictions.