Journal of Modern Optics

Refractive index enhancement in three-levelΛ-type atom with a saturation field: a dressed state analysis

C. Yang, Ying Gu, Lulu Wang, Qihuang Gong

Published Dec 15, 2006• 0 citations

Abstract

The paper reports investigations of refractive index enhancement (RIE) with zero absorption in a three-level Λ-type atom subject to a drive field, a saturation field and a probe field. As RIEs lie in the alternate points between emission and absorption peaks, one can predict their positions by employing dressed state theory and optical Bloch equations. The numerical calculations with dressed state analysis indicate that high refractive index enhancement appears mainly at two conditions: (i) off-resonance detuning of drive and saturation frequencies have the opposite sign; (ii) the saturation Rabi frequency is larger than the drive Rabi frequency. The analysis can be extended to multi-field multi-level atomic systems.

DOI: 10.1080/09500340600872804

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