Physical Review A
Angular dependence of an electromagnetically induced transparency resonance in a Doppler-broadened atomic vapor
P. R. S. Carvalho, Luı́s E. E. de Araujo, J. W. R. Tabosa
Abstract
We measured the dependence of the linewidth of an electromagnetically induced transparency resonance on the angle between coupling and probe beams in an atomic cesium vapor. We observed that the nonparallelism of the beams contributes strongly to a broadening of the coherent resonance, even for small angles on the order of a few milliradians. A numerical calculation that agrees qualitatively with the experimental results is also presented. We discuss a possible application of the observed effect for performing cold-atom velocimetry.