Abstract

Experiments in nonlinear optics and spectroscopy are often performed in atomic vapors, where the linewidths of the transitions of interest are dominated by Doppler broadening. In fact, several experiments on quantum coherent phenomena, such as lasing without inversion (LWI), and electromagnetically induced transparency (EIT), have been done in atomic vapors. Using the ideas of quantum coherence and interference, we propose a new scheme for obtaining sub- Doppler resolution at one transition of an inhomogeneously broadened, three-level atomic system, by use of an intense control field at the other transition. Analytical and numerical calculations are presented to delineate the mechanism responsible for this sub-Doppler resolution, and quantify the extent to which the Doppler broadening can be reduced. This Work represents a new class of phenomena in nonlinear optics, where the atomic Coherence induced by a control field is Used to influence inhomogeneous broadening.

© 1996 Optical Society of America