本論文探討基於電磁波引發透明的四波混頻系統之低光強脈衝的轉換效率。在本研究架設的冷銣原子之N型結構四能階系統中，可利用光強約80μW/cm^2的驅動脈衝，相當於在原子吸收截面積(3λ^2/2π)中約有60顆光子的能量，使四波混頻轉換效率可達到4%，此結果與利用Harris的理論預測所得之結果一致[Phys. Rev. Lett. 82, 4611 (1999)]。此外，本研究之電磁波引發透明機制的四波混頻系統，其轉換效率最大可達到46%。

We report on an experimental observation of electromagnetically induced transparency (EIT) based four-wave mixing (FWM) in the pulsed regime at low light levels. The FWM conversion efficiency of ~ 4% was observed in a four-level system of cold 87Rb atoms using a driving pulse with a peak intensity of only ~ 80 μW/cm^2, corresponding to an energy of ~ 60 photons per atomic cross section (3λ^2/2π). The experimental data are consistent with the theoretical predictions proposed by Harris and Hau [Phys. Rev. Lett. 82, 4611 (1999)]. Additionally, a maximum conversion efficiency of ~ 46% was demonstrated with the EIT-based FWM scheme.

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