原子受到碰撞時會影響其能階，使得電子躍遷譜線的中心頻率以及線寬發生改變。就我們所知，目前文獻上所記載的都是觀察原子氣體不同氣壓對譜線所造成的影響，而本論文則是分別控制原子氣室溫度以及指型冷凝部位溫度，想藉此觀察改變氣室溫度跟改變原子蒸氣壓是否會對譜線造成不一樣的影響。

在本論文的實驗裡，我們觀測的是銫原子6S-8S超精細結構雙光子躍遷的「譜線頻移」以及「譜線增寬」現象。為了量測這微小的變化，我們自製了一台頻率穩定度小於2 kHz的穩頻外腔式半導體雷射。從我們的實驗數據中發現：當原子氣室溫度固定，指型冷凝部位溫度上升時，躍遷中心頻率有紅移現象，譜線增寬；若指型冷凝部位溫度固定，讓原子氣室溫度上升，則躍遷中心頻率是藍移現象，譜線同樣是增寬。

除此之外，我們也做了入射光離器壁不同距離對躍遷中心頻率影響的實驗，我們發現入射光離器壁愈近，躍遷中心頻率愈高。我們嘗試利用銫原子電偶極矩以及感應電偶極矩之間的作用來解釋實驗中觀察到的現象，但是實驗結果跟我們理論預測的不符，因此尋找這個現象的原因便成了未來實驗的目標之一。

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