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A Knob for Changing Light Propagation from Subluminal to Superluminal

G. S. Agarwal·Tarak Nath Dey·Sunish Menon
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Abstract

We show how the application of a coupling field connecting the two lower metastable states of a lambda-system can produce a variety of new results on the propagation of a weak electromagnetic pulse. In principle the light propagation can be changed from subluminal to superluminal. The negative group index results from the regions of anomalous dispersion and gain in susceptibility.

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G. S. Agarwal, Tarak Nath Dey, Sunish Menon. 2001-06-19. A Knob for Changing Light Propagation from Subluminal to Superluminal. https://doi.org/10.1103/physreva.64.053809

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