We report the generation of nonclassical narrowband photon pairs via the spontaneous four-wave mixing process in a cold Rubidium (87Rb) cloud prepared in a magneto-optical trap. The generated photon pairs exhibit strong violation of the Cauchy-Schwarz inequality by a factor of 625 ± 45, confirming nonclassical correlation between the photons. The biphoton wave packets, measured for several different experimental conditions, are in good agreement with the theoretical results.
Bibliographical noteFunding Information:
We would like to thank Shengwang Du, Hoonsoo Kang, Jung-Bog Kim, Han-Seb Moon, Jianming Wen, and Hoon Yu for many fruitful discussions. This work was partially supported by the National Research Foundation of Korea (Grants No. 2011-0021452 and No. 2013R1A2A1A01006029). Y.-W. C. and J.-C. L. acknowledge support from the National Junior Research Fellowship (Grants No. 2011-0010895 and No. 2012-000741, respectively). K-K.P. acknowledges support from Global Ph. D. Fellowship by National Research Foundation of Korea (Grant No. 2011-0030856).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)