Journal of Physics B Atomic Molecular and Optical Physics
Sign reversal of Hanle electromagnetically induced absorption with orthogonal circularly polarized optical fields
Nibedita Ram, M. Pattabiraman
Abstract
We study by computation and experiment an electromagnetically induced absorption resonance in the Hanle configuration with a transverse magnetic field on a closed F g → F e = F g +1 transition with co-propagating orthogonal circularly polarized probe and coupling optical fields. At high coupling field intensities, the Hanle resonance changes sign due to a shift in atomic population from Zeeman sublevels associated with a probe field cyclic transition to sublevels associated with a coupling field cyclic transition at zero magnetic field. We also show that a similar sign reversal does not occur for π-polarized and σ-polarized coupling fields.