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Superluminal in Doppler broadened two-level atomic systems in magnetic field

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

Published Aug 1, 2009• 0 citations
Publisher

Abstract

A method to control the group velocity of light is proposed. It shows that by changing the magnetic field intensity and vapor temperature, the group velocity of light can be controlled in an appropriate region.
DOI
10.1109/cleopr.2009.5292495

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We have shown that quantum interference in a driven quasi-degenerate two-level atomic system can be controlled by an externally applied magnetic field. We demonstrate that the mechanism of optical control is based on quantum interference, which allows one to implement both electromagnetically induced transparency and electromagnetically induced absorption in one atomic system. Dispersion of such the medium allows one to control group velocity of propagation of light pulses be ultra-slow or superluminal via applied magnetic field.