Electromagnetically induced absorption in Λ-three-level system driven by bichromatic coupling field

摘要

The probe absorption spectrum of the Λ-three-level system driven by bichromatic coupling field and weak probe field is investigated. We obtain the probe absorption spectra for different frequency detunings of coupling field by solving the density matrix equation and numerical analysis. Three electromagnetically induced absorption (EIA) peaks are simultaneously observed in the absorption profile of probe field. We report the dependence of position and relative intensity of EIA on the frequency detuning of the bichromatic coupling field. The results show that central EIA always appears at the resonant frequency of probe field, with the constant intensity. The position of the secondary EIA vary with the frequency detuning of coupled field, and the intensity of the absorption peaks decrease with the increasing detuning.