Journal of the Optical Society of America B

ac Stark splitting and parametric resonances in a two-level system driven by a strong amplitude-modulated optical field

Michael Z. Smirnov

Published Jan 1, 1994• 6 citations

Abstract

The parametric resonances and the quasi-level structure of an atom strongly driven by a near-resonant amplitude-modulated optical field are studied theoretically. An approximate analytical solution of the density-matrix equations of motion is obtained for two-level and three-level atoms. Based on this solution the quasi-level shifts are analyzed, and the conditions for the quasi-levels to cross each other are derived. Expressions are given for the probe-wave absorption/gain spectrum near the parametric resonance and far from it. It is pointed out that the parametric resonances appear when the pumping field sidebands are tuned to resonance with some transitions among the quasi-levels.

DOI: 10.1364/josab.11.000109

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