本研究使用加熱爐管加熱鈉金屬至350°C產生足夠的鈉蒸氣於爐管中，並維持內部氣壓在4-6torr，使原子互相撞擊產生實驗所需的Na2，在實驗中使用了兩種不同的偵測方法來驗證我們的三能階系統。相較於先前的研究，我們此次分別使用兩台超短線寬雷射(Coherent 699 Ring-Dye Laser & Coherent 899 Ti:Sapphire Laser)作為激發光源，建立了一階梯式三能階系統，其能階態分別是基態X1Σg+、中間態A1Σu+和激發態41Σg+。
首先我們使用染料雷射做為泵浦雷射，調整至共振頻率使鈉分子從X1Σg+躍遷至A1Σu+，並配合所選頻率調整鈦藍寶石雷射，將鈉分子再次從A1Σu+躍遷至41Σg+。接著我們利用單光儀量測電子回到中間態與基態的螢光，藉由所得到的雷射激發光譜的譜線進行分析，並與實驗模擬所得的波長和強度與實際結果進行比較，驗證雷射頻率是否與我們預期的躍遷能階相同。另一方面，利用一組帶有濾光片的光電倍增管，量測經由內轉換從高能階單重態碰撞至高能階三重態最後返回基態的螢光，確認三能階系統的建立與否。
經由上述完整的實驗分析結果，我們可以清楚標定出多組三能階系統X1Σg+ (2,37) → A1Σu+(21,38) → 41Σg+ (11,37)、X1Σg+ (2,11) → A1Σu+(21,12) → 41Σg+ (12,13)和X1Σg+ (2,21) → A1Σu+(9,20) → 41Σg+ (3,19)等，同時我們也比較了因不同躍遷途徑對應不同的法蘭克-康登常數對於OODR訊號的影響，當法蘭克-康登常數較大時，我們能得到的OODR訊號也會較強，與理論預期相符合。而經由以上多組數據的研究，我們利用此三能階系統，架設一量子干涉實驗系統，量測雙原子鈉分子系統中的電磁誘發透明現象。我們將染料雷射作為探測光並將光強衰減至奈瓦等級，藉由掃描鈦藍寶石雷射頻率的同時，觀察染料雷射在穿透氣態鈉原子分子的光強變化，並成功觀測到電磁誘發透明的現象。

We first built a five arm heat pipe to heat the sodium metal up to 350°C and keep the system at low pressure around 4-6 torr. We tune the Laser frequency to excite the sodium dimer from the ground state (X1Σg+) to the intermediate state (A1Σu+). By collecting the Laser induced fluorescence (LIF), we can label the exact rotational and vibrational quantum number for the intermediate level. By using another laser, which is counter-propagate with the first laser to excite the molecules from intermediate state (A1Σu+) to upper state (41Σg+), we can also label the quantum number for the upper level by the same method mentioned above. Furthermore, we use optical-optical double resonance (OODR) to examine our transition results, which also matched with our conclusions. By establishing the three-level system, now we can measure the quantum interference in sodium dimer. In our following experiment, we scanned the frequency of Ti:Sapphire and measured the transparent power of dye laser. We successfully observed the electromagnetically induced transparency (EIT) signals in our system.

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