在原子光譜學中稱為電磁誘發透明 (electromagnetically induced transparency EIT）的幫助下，本論文研究了在銫原子尺度中的量子干涉現象。EIT 是通過引入另一個電磁場消除了共振吸收，從而在不透明材料中產生具有小於自然線寬的窄透明窗口。以一種可以想像的方式來解釋 EIT 的初步想法是，當另一個光源參與作用時，光束穿過介質後變得更亮。EIT 發生的條件將在理論上得出，並在本論文中透過實驗觀察。梯形的EIT架構是用來研究含超精細結構的銫原子從6S-6P-11S在室溫下的三能階系統並且探討在光場具有偏振下的相依性。兩道重疊線偏振光的相對偏振角度會對於觀察到的峰值訊號會有顯著的影響。在此篇論文中我們把相對角度訂為0，45與90度。當角度為90度時，44’3’’ 的峰值比0度高出約6.5倍。同時，44’4’’ 的高度會隨著兩道線偏振光的相對偏振角度增加而稍微的下降。

The quantum interference phenomenon in the cesium atomic scale is considered here with the help of a powerful technique in atomic spectroscopy termed as electromagnetically induced transparency (EIT). EIT eliminates a resonant absorption by introducing another electromagnetic field, resulting in a narrow transparency window with sub-natural linewidth in an opaque material. An imaginable way to pick up some first ideas about EIT is by imaging that a light beam passes through a medium getting brighter when another overlapping light source is introduced. The conditions for EIT to happen will be derived theoretically and observed experimentally in this thesis.
An experimental setup for the ladder-type EIT is exploited to study the hyperfine levels of 133Cs 11S1/2 state, which involves the 6S1/2-6P3/2-11S1/2 transition under room temperature, with polarization dependence. The change of the relative angle between two polarization planes of the two linearly polarized fields results in a significant change in the peak height of the observed EIT spectra. That relative angle is set at 0o, 45o, and 90o in this experiment. As the relative angle at 90o the intensity of peak 44′3′′ is 6.5 times higher than that of the relative angle at 0o. Meanwhile, the intensity of peak 44′4′′ slightly decreases as increasing the relative angle between the two polarizations of the probe and coupling fields.

[1]. S. E. Harris, J. E. Field and A. Imamoğlu, Nonlinear optical processes using electromagnetically induced transparency, Phys. Rev. Lett. 64, 1107 (1990).
[2]. K. H. Weber and C. J. Sansonetti, Accurate energies of nS, nP, nD, nF, and nG levels of neutral cesium, Phys. Rev. A 35, 4650 (1987).
[3]. K. J. Boller, A. Imamoğlu and S. E. Harris, Observation of electromagnetically induced transparency, Phys. Rev. Lett. 66, 2593 (1991).
[4]. D. F. Phillips, A. Fleischhauer, A. Mair, R. L. Walsworth and M. D. Lukin, Storage of Light in Atomic Vapor, Phys. Rev. Lett. 86, 783 (2001).
[5]. G. S. Agarwal, Inhibition of spontaneous emission noise in lasers without inversion, Phys. Rev. Lett. 67, 980 (1991).
[6]. A. K. Mohapatra, T. R. Jackson and C. S. Adams, Coherent Optical Detection of Highly Excited Rydberg States Using Electromagnetically Induced Transparency, Phys. Rev. Lett. 98, 113003 (2007).
[7]. M. Mack, F. Karlewski, H. Hattermann, S. Höckh, F. Jessen, D. Cano and J. Fortágh, Measurement of absolute transition frequencies of 87Rb to nS and nD Rydberg states by means of electromagnetically induced transparency, Phys. Rev. A 83, 052515 (2011).
[8]. S. E. Harris, Electromagnetically induced transparency, Phys. Today 50, 36 (1997).
[9]. U. Fano, Description of States in Quantum Mechanics by Density Matrix and Operator Techniques, Rev. Mod. Phys. 29, 74 (1957).
[10]. J. Weiner and P. T. Ho, Light-Matter Interaction: Fundamentals and Applications. Wiley, 2008.
[11]. C. J. Foot, Atomic physics. Oxford University Press, Oxford, 2005.
[12]. P. van der Straten and H. Metcalf, Atoms and Molecules Interacting with Light: Atomic Physics for the Laser Era. Cambridge University Press, Cambridge, 2016.
[13]. D. A. Steck, "Cesium D Line Data" avalable at https://steck.us/alkalidata/
(reversion 2.1.4, 23 December 2010)
[14]. Z.-S. He, J.-H. Tsai, M.-T. Lee, Y.-Y. Chang, C.-C. Tsai and T.-J. Whang, Determination of the Cesium 11s 2S S1/2 Hyperfine Magnetic Coupling Constant Using Electromagnetically Induced Transparency, J. Phys. Soc. Jpn 81, 124302 (2012).
[15]. S. Shepherd, D. J. Fulton and M. H. Dunn, Wavelength dependence of coherently induced transparency in a Doppler-broadened cascade medium, Phys. Rev. A 54, 5394 (1996).
[16]. Z.-S. He, J.-H. Tsai, Y.-Y. Chang, C.-C. Liao and C.-C. Tsai, Ladder-type electromagnetically induced transparency with optical pumping effect, Phys. Rev. A 87, 033402 (2013).
[17]. Y.-q. Li and M. Xiao, Observation of quantum interference between dressed states in an electromagnetically induced transparency, Phys. Rev. A 51, 4959 (1995).
[18]. P. M. Farrell and W. R. MacGillivray, On the consistency of Rabi frequency calculations, J. Phys. A: Math. Gen. 28, 209 (1995).
[19]. H. S. Moon and H.-R. Noh, Polarization dependence of double-resonance optical pumping and electromagnetically induced transparency in the 5S1/2-5P3/2-5D5/2¬ transition of 87Rb atoms, Phys. Rev. A 84, 033821 (2011).
[20]. C. Cohen-Tannoudji and S. Reynaud, Dressed-atom description of resonance fluorescence and absorption spectra of a multi-level atom in an intense laser beam, J. Phys. B: At. Mol. Opt. Phys. 10, 345 (1977).
[21]. M. Krainska-Miszczak, Alignment and orientation by optical pumping with pi polarised light, J. Phys. B: At. Mol. Opt. Phys. 12, 555 (1979).