Physical Review A
Origin of the “blueshift” in selective reflection spectroscopy and its partial compensation by the local-field correction
T. A. Vartanyan, Antoine Weis
Abstract
The theory of selective reflection from the interface of a dielectric medium and an atomic vapor is reconsidered. Both the local-field correction and the nonexponential decay of the electromagnetic field inside the vapor are accounted for in a purely analytical form. It is shown that the large influence of both effects on the shift of the spectral line is due to an interference between contributions from atoms moving towards the reflecting surface and from those moving away. We show that the local-field correction reduces the blueshift due to the field decay by one-third of its value. A simple formula relating the shift of the maximum of the reflection spectrum to the transition dipole moment and the number density of the atoms is given.