We present a theoretical formulation of the competition between electromagnetically induced transparency (EIT) and Raman processes. The latter become important when the medium can no longer be considered to be dilute. Unlike the standard formulation of EIT, we consider all fields applied and generated as interacting with both the transitions of the $\Lambda$ scheme. We solve the Maxwell equations for the net generated field using a fast-Fourier-transform technique and obtain predictions for the probe, control, and Raman fields. We show how the intensity of the probe field is depleted at higher atomic number densities due to the buildup of multiple Raman fields. Furthermore, we find that the generated fields and the input fields acquire oscillatory behavior as a function of the density of the medium due to dynamical coupling of the various Raman processes.

• Received 22 May 2006

DOI:https://doi.org/10.1103/PhysRevA.74.043805