摘要
We report the experimental generation of narrow-band paired photons through electromagnetically induced transparency and spontaneous four-wave mixing in a two-dimensional magneto-optical trap (2D MOT). By controlling the optical depth of the 2D MOT from 0 to 40, the temporal length of the generated narrow-band paired photons can be varied from 50 to 900 ns. The 'transition' between damped Rabi oscillation and group delay is observed undisputedly. In the damped Rabi oscillation regime, a violation factor of the Cauchy–Schwartz inequality as large as 6642 is observed. In the group delay regime, sub-MHz linewidth (~0.65 MHz) paired photons are obtained with a generation rate of about 0.8×105 s?1.
We report the experimental generation of narrow-band paired photons through electromagnetically induced transparency and spontaneous four-wave mixing in a two-dimensional magneto-optical trap (2D MOT). By controlling the optical depth of the 2D MOT from 0 to 40, the temporal length of the generated narrow-band paired photons can be varied from 50 to 900 ns. The 'transition' between damped Rabi oscillation and group delay is observed undisputedly. In the damped Rabi oscillation regime, a violation factor of the Cauchy–Schwartz inequality as large as 6642 is observed. In the group delay regime, sub-MHz linewidth (~0.65 MHz) paired photons are obtained with a generation rate of about 0.8×105 s?1.
基金
Supported by the National Natural Science Foundation of China under Grant Nos 11104085, 11125417, and 61378012, the Major Research Plan of the National Natural Science Foundation of China under Grant No 91121023, the State Key Program for Basic Research of China under Grant No 2011CB922104, the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China under Grant No IRT1243, and the SRFGS of South China Normal University.