為了與國立中央大學現有的 10.2 \textmu m 種子光源架構整合，本研究探討了一種新型的光學幫浦架構，其不同於加州大學洛杉磯分校（UCLA）利用 Er:YAG 幫浦 Fe:ZnSe 固態雷射來激發二氧化碳（$\text{CO}_2$）。本研究利用電光效應去架設 Q-switched Er:YLF 固態雷射，針對 $\text{CO}_2$ 氣體位於 2.7 \textmu m 的分子吸收，直接激發二氧化碳氣體。實驗中架設了一套主動調 Q 的 Er:YLF 雷射振盪器，並對其進行了光學特性量測。該振盪器採用 $\text{MgO:LiNbO}_3$ Pockels cell 進行主動調變，在輸出耦合鏡反射率為 98\%、重複頻率為 $2~\text{Hz}$ 的條件下，測得輸出脈衝能量為 270 \textmu J，脈衝寬度（半高全寬，FWHM）約為 $500~\text{ns}$。此外，透過自行設計與架設的 Czerny-Turner 光譜儀進行光譜測量，雷射中心發射波長約為 $2663~\text{nm}$，該波長與 $\text{CO}_2$ 的吸收光譜有重疊。隨後，本研究利用此 Er:YLF 雷射進行了 $\text{CO}_2$ 氣體的吸收測試。在 4N 高純度 $\text{CO}_2$ 氣體壓力達 $55~\text{psi}$ 的條件下，測量到吸收率達 $3\%/\text{cm}$。我們亦藉此嘗試估算了採用腔內幫浦（intra-cavity pump）架構所能達到的小訊號增益（small-signal gain）。儘管最終放大階段的參數最佳化仍在持續進行中，但本研究已成功驗證了 Er:YLF 腔內幫浦架構的技術可行性，為未來發展太瓦級（Terawatt， TW）$\text{CO}_2$ 雷射前級放大器提供了一項選擇。;This study investigates a different optical pumping scheme than that presented by UCLA， which uses Er:YAG-pumped Fe:ZnSe solid-state lasers to excite carbon dioxide (CO₂)， aiming to integrate it with the existing 10.2 \textmu m seed light source architecture at National Central University. This study proposes using an electro-optically Q-switched Er:YLF solid-state laser to excite CO₂ gas， specifically targeting the strong molecular absorption band at 2.7 \textmu m. An actively Q-switched Er:YLF oscillator was constructed and optically characterized. Employing a MgO:LiNbO3 Pockels cell for active modulation， the oscillator delivered a measured output pulse energy of 270 \textmu J from a 98\% output coupler and a pulse duration (FWHM) of around 500ns at a repetition rate of 2Hz. The spectral characterization via a custom-designed Czerny-Turner spectrometer estimate a central emission wavelength of $2663~\text{nm}$， which overlaps with the $\text{CO}_2$ absorption spectrum. Subsequently， CO₂ absorption was tested using this Er:YLF laser. At a maximum pressure of 55 psi for pure 4N CO₂ gas， the absorption rate reached 3\%/cm. We also attempted to estimate the small-signal gain that could be reached from using an intra-cavity pump architecture. While optimization of the final amplification stage is still underway， this work demonstrates the technical feasibility of the Er:YLF intracavity pumping scheme and provides an option for developing terawatt (TW) $\text{CO}_2$ laser preamplifiers.
