MA Zhe1,2, CHANG Hong1,3, ZHANG Shou-gang1,3

(1. National Time Service Center, Chinese Academy of Sciences, Xi'an 710600, China;

2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China;

3. Key Laboratory of Time and Frequency Primary Standards, National Time Service Center,

Chinese Academy of Sciences, Xi'an 710600, China)

Abstract: We investigated theoretically the EIT(electromagnetically induced transparency) effect and the accompanying Kerr nonlinear effect in Sr atomic system. The result shows that using the optical molasses as EIT medium we can get a very narrow EIT window and a strong Kerr nonlinear effect by using a weak probe beam. This result builds a theoretical basis for narrowing the line width of 689 nm laser and probing the frequency signal of 88Sr bosonic optics clock by using the EIT effect .

Key words: Sr atom; EIT(electromagnetically induced transparency) effect; Kerr nonlinear effect; Sr optical clock