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arXiv · 0711.4259

Coherent control of light field with electromagnetically induced transparency in a dark state Raman coherent tripod system

YongYao Li·HuaRong Zhang·YongZhu Chen·JianYing Zhou
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Abstract

The coherent superposition of two-atomic levels induced by coherent population trapping is employed in a standard $Λ$ type scheme to form a tripod-like system. A weak probe pulse scanning across the system is shown to experience a crossover from absorption to transparent and then to amplification. Consequently the group velocity of the probe pulse can be controlled to propagate either as a subluminal, a standard, a superluminal or even a negative speed. It is shown that the propagation behavior of the light field is entirely determined and controlled by the initial states of the coherent superposition.

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YongYao Li, HuaRong Zhang, YongZhu Chen, JianYing Zhou. 2008-01-02. Coherent control of light field with electromagnetically induced transparency in a dark state Raman coherent tripod system. https://arxiv.org/abs/0711.4259

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