Role of transfer of coherence in the enhanced absorption Hanle effect with two optical fields

The enhanced absorption Hanle effect has been studied for a closed transition Jg = 2 → Je = 3 with a transverse magnetic field in the presence of a coupling optical field. From an analysis of the individual probe and coupling field absorption profiles, it is shown that the Hanle electromagnetically induced absorption is governed by the transfer of Δm = 2 and Δm = 1 Zeeman coherences from the excited state to the ground state via spontaneous emission. The individual coherence contributions are governed by the intensity ratio of the optical fields. We show by computation and experiment that the magnetic field dependence of the forward scattered intensity can be used to distinguish the transfer of coherence contributions to the Hanle profile. © 2009 IOP Publishing Ltd.