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arXiv · 1311.5292

Low-light-level four-wave mixing by quantum interference

Chang-Kai Chiu·Yi-Hsin Chen·Yen-Chun Chen·Ite A. Yu·Ying-Cheng Chen·Yong-Fan Chen
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Abstract

We observed electromagnetically-induced-transparency-based four-wave mixing (FWM) in the pulsed regime at low light levels. The FWM conversion efficiency of 3.8(9)% was observed in a four-level system of cold 87Rb atoms using a driving laser pulse with a peak intensity of approximately 80 μW/cm^2, corresponding to an energy of approximately 60 photons per atomic cross section. Comparison between the experimental data and the theoretical predictions proposed by Harris and Hau [Phys. Rev. Lett. 82, 4611 (1999)] showed good agreement. Additionally, a high conversion efficiency of 46(2)% was demonstrated when applying this scheme using a driving laser intensity of approximately 1.8 mW/cm^2. According to our theoretical predictions, this FWM scheme can achieve a conversion efficiency of nearly 100% when using a dense medium with an optical depth of 500.

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Chang-Kai Chiu, Yi-Hsin Chen, Yen-Chun Chen, Ite A. Yu, Ying-Cheng Chen, Yong-Fan Chen. 2014-02-07. Low-light-level four-wave mixing by quantum interference. https://doi.org/10.1103/physreva.89.023839

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