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Advances in Optical Sciences Congress

Observation of slow light and superluminal in Cs atomic vapor

Yundong Zhang, Shuangqiang Liu, Hao Wu, Zhusong He, Ping Yuan

Published Jan 1, 2009• 0 citations
Publisher

Abstract

Slow light and superluminal were both observed in Cs atomic vapor without any couple field. By only changing the signal modulate frequency, the light propagation changes from superluminal to slow light.
DOI
10.1364/sl.2009.jwa27

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Slow and superluminal group velocities can be observed in any material that has large normal or anomalous dispersion. While this fact has been known for more than a century, recent experiments have shown that the dispersion can be very large without dramatically deforming a pulse. As a result, the significance and nature of pulse velocity is being reevaluated. In this review, we discuss some of the current techniques used for generating ultra-slow, superluminal, and even stopped light. While ultra-slow and superluminal group velocities have been observed in complicated systems, from an applications point of view it is highly desirable to do have this done in a solid that can operate at room temperature. We describe how coherent population oscillations can produce ultra-slow and superluminal light under these conditions.
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