Splitting of electromagnetically induced absorption signal in a five-level V-type atomic system

Abstract

Electromagnetically induced absorption (EIA) and velocity-selective transparency peaks are observed in the probe absorption signal of V-type five-level atomic systems interacting with copropagating control and probe fields. At high control beam intensity, a splitting of EIA occurs. The experiment shows similar results for both Rb87 and Rb85 isotopes at room temperature. A density matrix-based theoretical model of this five-level system has been developed and solved numerically under steady-state condition. The simulated spectra agree quite well with the experimental findings. An analytic expression for the probe response is derived and used to find out the causes for the splitting of EIA.