本實驗使用熱管爐加熱至350⁰C以產生足夠的鈉蒸氣，再藉由碰撞形成我們所需要的Na2，而後使用氬離子雷射將納分子產生X1Σg+→B1u的躍遷，並觀察其螢光訊號，此為雷射誘發螢光光譜法，由於學長還剩下氬離子雷射457.9nm未完成，以該雷射譜線實驗雷射誘發螢光光譜，再藉由文獻中的分子常數分析該躍遷的轉、振能階，可以比對出兩組不同的躍遷譜線，分別為：B1u(27,31) →X1Σg+(7,31)與B1u(28,43) →X1Σg+(7,43)。
在雙光子共振光譜法，因二極體雷射的波長範圍有限，所以先從文獻中的分子常數計算出B1u → 31g躍遷的能階，再使用二極體雷射調整至合適的波長後執行掃描。一共觀察到3個不同的轉、振能階，其能量的標準差約在300MHz，並且以Voigt函數擬合該訊號，可得譜線的高斯線寬約為1GHz，勞倫斯線寬約為100MHz。爾後針對壓力變化與雷射強度變化的雙光子共振光譜，以與時間相關的微擾理論計算與二能階系統，預計將可觀察到碰撞增寬與強度增寬的效應。在雷射強度的變化下，其吸收率正比於雷射強度，與理論預測相當，但未觀察到強度增寬的現象，氬離子雷射強度由188mW改變至5mW，不論是針對高斯線寬還是勞倫斯線寬上都沒有明顯的相關性，推測是由於在該雷射能量的不準度(~10GHz)已經遠遠大於都卜勒線寬與強度增寬的效應，導致沒有觀察到強度增寬的現象。而在壓力改變的變化下(0.6 torr~4 torr)，其勞倫斯線寬正比於熱管爐的壓力，並且由此量測出31g的自然線寬為50~75MHz(針對不同的轉、振能階自然線寬所不同)，與前人使用脈衝雷射量測31u的結果(13)(150MHz~240MHz)在同一個數量級，後續的参光子共振光譜中其線寬約為100MHz，驗證了使用與壓力相關的雙光子共振光譜來量測其自然線寬的一致性。
最後由Ti-Sapphire雷射完成参光子共振光譜法，本實驗一共使用了3種不同形式的参光子共振光譜，分別是Λ-形、V-形和Y-形，並且觀察到了13個不同的轉、振能階。在Λ-形所觀察到的訊號，能量標準差約在50MHz，而線形為勞倫斯函數，線寬約為100MHz，與使用雙光子共振法中的勞倫斯線寬一致。V-形的参光子共振光譜法中，找到了一組P、R line期限寬較Λ-形参光子共振光譜寬，約為250MHz，而能階的標準差約在50MHz。Y-形参光子共振光譜，能量的標準差約為300MHz，而線寬為約1GHz，與雙光子共振光譜雷同，並且在訊號中發現可重複性的凹陷，並且其凹陷與中心的距離與二極體雷射的調變量有關。最後執行與雷射光強度相關的V形参光子共振光譜實驗，在該實驗中有兩組不同的實驗方式一是改變氬離子雷射強度固定Ti-Sapphire，另一則是改變Ti-Sapphire固定氬離子雷射，改變的範圍由25mW~100mW，中觀測到其訊號與雷射光強度成正比，在線寬上，有觀察到強度增寬效應其變化與雷射強度成正比變化量約由240MHz~300MHz。

Using the method of laser-induced fluoresce (LIF) with argon laser at 457.9nm, two ro-vibration quantum levels of Na2 B1u can be labeled, which are B1u(27,31) →X1Σg+(7,31) and B1u(28,43) →X1Σg+(7,43)
Optical-optical double resonance (OODR) could been done by using diode laser and argon laser. The transitions are X1Σg+ →B1u  21g (or 31g). There are three different levels which have been labeled. The standard deviation of term value is about 300MHz. The intensity of OODR signal were measured by varying argon laser power. The absorption rate of sodium dimer is proportional to the power of argon laser. And this phenomenon can be predicted by theory. But the effect of power broadening was not observed. Using the Voigt function fitting the OODR signal, the FWHM stay unchanged at about 1GHz(Gaussian linewidth), and the Lorentzian linewidth stay at about 100MHz. We thought that the energy uncertainty of the argon in our experiment was too large compare to the linewidth. For the pressure-dependent of OODR signal was observed. The Lorentzian linewidth of signal is proportional to the pressure. This phenomenon agrees with theory as well, and this might be a way to measure the nature linewidth of molecules.
Finally, by using Ti-sapphire laser, three different types of all-optical triple resonance (AOTR) have been done, which are Λ-, V- and Y-type. Thirteen different levels have been labeled. For term value the standard deviation was about 50MHz in both Λ-type and V-type AOTR. Besides, the Lorentzian linewidth was about 100MHz in Λ-type, 250MHz in V-type. For Y-type AOTR the standard deviation of term value was about 300MHz, FWHM was about 1GHz which is similar to the OODR signal. Furthermore, notice that there exists a dip in the signal of Y-type AORT, and the separation between the dip and the peak center is proportional to the detuning of diode laser. For power depend V-type AOTR. The amplitude of AOTR signal is proportional to the power of Argon/Ti-sapphire laser. Furthermore, the analysis of linewidth had been done. The linewidth of V-type AOTR was proportional to the power of Argon/Ti-sapphire laser. The change of laser power was from 100mW to 25mW, and this change lead to variation of linewidth form 240MHz to 300MHz.

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