本論文探討在冷銣原子系統下基於電磁波引發透明機制建立雙 Λ電磁波引發透明的同調光操控。我們藉由改變雙 Λ電磁波引發透明中四道光的相對相位，分別是探測光、耦合光、驅動光、信號光，來研究在不同的相對相位下探測光及信號光的轉換效率。由於在此系統下探測光在不同相對相位下會將能量轉給信號光，同樣的信號光也會將能量轉給探測光，因此研究發現在三光子調變90 MHz，即15Γ 下，這裡的 Γ 是指銣原子的自然線寬6 MHz，且探測光及信號光相同強度時，探測光轉給信號光的功率約探測光本身功率的63%，信號光轉給探測光的功率約信號光本身功率的53%，而在探測光及信號光強度比例為0.1 nW：400 nW時，探測光強度增加約700倍，但此時信號光強度是在違背微擾的條件下，可以發現信號光轉給探測光的功率約信號光本身功率的17.5%，即信號光轉換效率在探測光與信號光的比例相差很大的情形下，有明顯變差的情形，說明在不違背為擾條件下雙 Λ電磁波引發透明系統能有較好的轉換效率。

We report on experimental observation of electromagnetically induced transparency (EIT) based double-Λ EIT. We vary the relative phase of the applied laser fields to study the conversion efficiencies of the probe and the signal fields. In the experiment, the probe conversion efficiency of ≈63% was observed and the signal conversion efficiency of ≈53% at the three-photon detuning of 90 MHz. Here both the probe and signal powers were set to 1nW. When the ratio of the probe power to the signal power was 1:4000, the probe power approximatively increased seven hundred times.

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