Understanding asymmetry in electromagnetically induced transparency for 87Rb in strong transverse magnetic field

Velocity selective multiple two-photon dark and bright resonances in Potassium vapor

“…Adiabatic elimination works well to describe the bright resonance in the blue and red detuning regions. The exact line shape can be matched by considering the intervention of other excited states [29]. To the best of our knowledge, these observations of additional resonances and a smooth crossover from EIT to EIA have not been reported in previous EIT-EIA studies.…”

“…This allows for a fortuitous swapping of the transition pathways as will be shown in details in the following sections, which in turn is responsible for observing additional quantum interference signals reported in this article. We note that such swapping of the transition pathways is generally allowed in all physical systems where EIT-EIA phenomena is experimentally observed including well studied atomic systems such as Rb [28][29][30] and Cs [17]. Consequently, a group of atoms having velocity exceeding a critical velocity = pD v c k 2 hf , (where Δ hf = 461.7 MHz is the ground state hyperfine splitting, k is the wave vector) can create another two-photon resonance by interchanging the excitation pathways of probe and control beams as depicted in the figure 1.…”

Anti-relaxation coating-induced velocity-dependent population re-distribution in electromagnetically induced transparency

“…The application of magnetic field lifts up the degeneracy of the hyperfine levels that leads to multiple EIT sub-peaks. However, due to the involvement of large number of levels due to lifting of the degeneracy, the spectra shows absorption in place of transmission or some competition between them [20]. Such process are system specific and depends upon the polarization of the pump and probe beam in general.…”

“…One such process was reported in [21] where the strong population alignment was marked by the presence of bright resonance along with dark resonances in D 1 line of 87 Rb. While working with magnetic field the authors have shown in earlier works [20,22] that it is possible to resolve off-resonant process in a vapor cell in D 2 line of 87 Rb under certain pump probe configuration. Such off-resonant process was observed as absorption and it was found that by carefully tuning the power of the beam, absorption can be converted to transmission in a uncoated vapor cell.…”