On the Time Dependent Features of the Two-Colour Light Pulses Propagation in the Sodium Vapour

Abstract

The phase and group velocities of the pulsed light are suitably defined and calculated. So are the duration of both pulses, probe and coupling, and their energies as a function of the travelled distance. The time evolution, for a given distance, of the dressed atom state is described by the Liouville-von Neumann equation for the density matrix.

Three-Colour Excitation of D1Transition in Cold Rubidium Atoms

“…The light storage effect is evident in the drive field as well, as we have designated. Through the first induction period, the probe (Ω p ) and the drive (Ω r ) show good resemblance to the two-colour EIT effect [13]. It is worth mentioning that the Raman coherence does not vanish for a long time.…”

“…[5] and references therein). In recent papers, we have analysed the quantum interference effect in the two-(299) -colour excitation of the sodium atom and the time dependent features of the two--colour pulse propagation [11][12][13]. We have found that during the time dependent excitations, the coupling field enhances under the two-photon EIT condition.…”