Theory of self-induced transparency in a focused light beam
Kozlov V. V., Fradkin E. E.
A theory is derived for the self-induced transparency of Gaussian light beams. A solution found in the single-mode approximation is a product of McCall-Hahn soliton and a Laguerre-Weber function. The carrier frequency of the pulse is redshifted from the transition line. The shift is inversely proportional to the radius of the minimum light spot.