Chinese Physics Letters
Non-Classical Correlated Photon Pairs Generation via Cascade Transition of 5S1/2–5P3/2–5D5/2in a Hot85Rb Atomic Vapor
Wei Zhang, Dong-Sheng Ding, Jian-Song Pan, Bao-Sen Shi
Abstract
We experimentally prepare the non-classical correlated photon pairs at the wavelengths of 780 and 776 nm via the cascade transition of 5S 1/2 –5P 3/2 –5D 5/2 in a hot 85 Rb 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.