本論文鎖定探測光在銫原子D2 line的超精細結構，並掃描耦合光到8s的超精細結構，觀測銫原子階梯式電磁誘發透明現象。
實驗訊號要考慮速度群、綴飾態、多重中間態等因素的影響，我們考慮這些因素，並進行理論模擬，在訊號的相對位置上，我們以綴飾態模型去分析，並得到相當不錯的擬合結果，在訊號的強度上我們加入雙光子躍遷機率與光泵浦效應進行模擬，但無法擬合得很好，最後我們發現當基態一樣時，即使探測光鎖定在不同能階亦可以用一組參數去擬合訊號強度。
接著我們觀測探測光強度對電磁誘發透明的影響，我們也做加入光泵浦效應與否之模擬的比較，當探測光強度增加時，對比模擬的訊號圖，我們可以發現其對訊號的影響並不是線性的，探測光強度增加時，增強吸收訊號亦會越來越強。並且我們利用較強的探測光，成功觀測綴飾態的存在，但在實驗的訊號位置上與理論模擬則有些許差距。

This thesis analyzed the line intensities of the electromagnetically induced transparency in a three-level cascade-type system of cesium. The probe beam lock on different Cs D2 line hyperfine transitions and the coupling laser scanned over the 8s states to record the EIT spectra.

Due to the effects of the atoms with different velocity, the dressed states, multi-level intermediate states, wavelength miss matching, have to take into account for construction the simulation. The position of the EIT signals could fit well with the dressed state theory. But the amplitudes of the EIT signals cannot be well fitted, even we took the two photon transition probability and the optical pumping effect into account. Finally, we found that if the ground state was the same, we could use a set of parameters to fit the amplitudes even the probe beam locked in different transitions.

The signal of electromagnetically induced transparency affected by the power of probe beam was observed. The simulation with optical pumping effect is considered. Comparing the simulation results, we found that the effect on the signal was not linear as the power of probe beam increasing so does the enhanced absorption increasing too. And the dressed states can be observed with high power probe beam. However, the position of the experimental signals was a little different from the theory simulations.

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