Acta Physica Sinica

Effect of spontaneously generated coherence on absorption and dispersion in probe laser

Yan Xiang-An, Jianping Song, Bao-yin Yin, Jiang Wen-Juan, Zhen Huai-Bin, Zhang Yan-Peng, (1)西安交通大学电子物理与器件教育部重点实验室，西安 710049; (2)西安交通大学电子物理与器件教育部重点实验室，西安 710049；陕西师范大学物理学与信息技术学院，西安 710062; (3)西安交通大学电子物理与器件教育部重点实验室，西安 710049；西安工程大学理学院，西安 710048

Published Jan 1, 2008• 10 citations

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Abstract

A theoretical investigation is carried into the effect of spontaneously generated coherence on absorption and dispersion in probe laser of Y-type atom system. It is found that the electromagnetically induce transparency window in the system narrows gradually as the spontaneously generated coherence intensifies. Moreover, the anomalous dispersion appears and the absorption changes from negative value to positive valve at resonance. At the same time, the absorption is zero or negative near resonance when the relative strength of the coupling field and pump field are different, and the atomic medium shows positive absorption when the two fields are exattly or nearly equal and close.

DOI: 10.7498/aps.57.3538

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