本論文利用電磁誘發透明的現象研究室溫銫原子62S1/2->62P3/2->82S1/2躍遷，並針對其譜線線形、譜線間距和譜線線寬做測量分析與討論。由於探測雷射與耦合雷射光源之間的波長不匹配因子κ(=852.3/794.6)，解釋室溫電磁誘發透明光譜的訊號間的相對位置偏移，即ΔEhfs(1-κ)；舉例來說：62P3/2超精細結構F’=4和5產生電磁誘發透明的頻率偏移為18.23 MHz。然後以耦合至82S1/2超精細結構F’’=3和4的電磁誘發透明頻率間距來推算出82S1/2超精細結構常數，其中七組數值為218.62±0.44 MHz。接下來透過積分原子速度群分布來解釋電磁誘發透明譜線增強吸收線形和其線寬變窄的現象。最後探討耦合雷射光強度對電磁誘發透明窗口寬窄的影響，其中可以於Ωc=10.57 MHz觀察到小於自然線寬(Γ2=5.22 MHz)的穿透窗口。我們實驗中發現，當調弱耦合雷射的拉比頻率時，可得到最小線寬為1.96(28) MHz。

This thesis studies the phenomena of ladder-type electromagnetically induced transparency (EIT), including line shape, frequency position and linewidth of the transmission signals, on 62S1/2->62P3/2->82S1/2 transition in room temperature cesium cell. The relative frequency of transmission signals are well explained by introducing the wavelength mismatch factor κ(=852.3/794.6) between the probe and coupling laser, i.e. ΔEhfs(1-κ). For example, the relative frequency of the transmission signal through the intermediate states │62P3/2, F’=3> and │62P3/2, F’=4> is about 18.23 MHz. The hyperfine constant of 82S1/2 is calculated by directly measured frequency difference between the transmission signals coupling to │82S1/2, F”=3> and │82S1/2, F”=4>, as following 218.62±0.44 MHz. Additionally, the enhanced absorption dips on both wings and narrowing effect on linewidth can be well explained while considering the integration of velocity groups. Finally, we investigate the linewidth of transmission signal by adjusting the coupling Rabi frequency. Subnatural linewidth below Γ2(=5.22 MHz) of EIT is obtained even though the coupling Rabi frequency is as large as 10.57 MHz. Furthermore, the narrowest EIT linewidth is 1.96(28) MHz by lowering the coupling Rabi frequency.

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