Autler-Townes doublet

As can be seen, the observations of Fig. 3 fit the pattern of a well resolved Autler-Townes doublet. The separation of the two components is smallest when the detuning is smallest it then gives a direct measure of the Rabi frequency of the S-field transition. 

The two satellites on either side of the main transition are called an Autler-Townes doublet after the names of those who first observed them [473], They were, however, predicted at an earlier date by Mollow [474]. An elegant method of calculating the fluorescence profile was described by Cohen-Tannoudji and Avan [475]. A very full discussion of how to represent this problem, including the central elastic component, the inelastic contributions and the sidebands, can be found in lecture notes by Co hen-Tannoudji [476]... 

The previous few examples show that, under coherent illumination, one can no longer consider observed spectral intensities as purely characteristic of the atom, since the properties of the Autler-Townes doublet depend on the laser intensity, and the profile of a laser-excited autoionising line will in general possess a shape unrelated to that of an atom excited by a weak source. 

S. Menon, G. Agarwal, Gain components in the Autler-Townes doublet from quantum interferences in decay channels, Phys. Rev. A 61 (1999) 013807. 

WoUenhaupt M, Assion A, Bazhan O, Horn C, Liese D, Sarpe-Tudoran C, Winter M, Baumert T (2003) Control of interferences in tm Autler-Townes doublet symmetry of control parameters. Phys Rev A 68 015401... 

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