Dispersion properties of electromagnetically induced transparency under the Doppler broadening

The influence of heat motion of atoms in gaseous media on the features of manifestation of electromagnetically induced transparency is investigated. Taking into account elastic and inelastic collisions, fairly general and compact analytical relations are derived for the absorption and refraction coefficients of the probe wave in the presence of high-power inducing radiation, resonant to the adjacent atomic transition. It is shown, that occurrence of narrow resonance structures in the Doppler absorption and refraction profile is due to "overlap" of effective resonance velocities of atoms. The atomic level splitting in the strong wave field is uniformly analyzed in the entire intensity range. Interference transparency in a particular region of the Doppler profile is found to be accompanied by high resonance dispersion of the refraction coefficient, which is important for generating slow radiation and controlling its parameters. © 2007 Springer Science+Business Media, Inc.